13271220 has 72 divisors (see below), whose sum is σ = 42633864. Its totient is φ = 3330048.

The previous prime is 13271213. The next prime is 13271227. The reversal of 13271220 is 2217231.

It is an interprime number because it is at equal distance from previous prime (13271213) and next prime (13271227).

It can be written as a sum of positive squares in 4 ways, for example, as 224676 + 13046544 = 474^2 + 3612^2 .

It is a super-2 number, since 2×13271220² = 352250560576800, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 13271193 and 13271202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13271227) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 892 + ... + 5228.

It is an arithmetic number, because the mean of its divisors is an integer number (592137).

Almost surely, 2^13271220 is an apocalyptic number.

13271220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 13271220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21316932).

13271220 is an abundant number, since it is smaller than the sum of its proper divisors (29362644).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

13271220 is a wasteful number, since it uses less digits than its factorization.

13271220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4369 (or 4364 counting only the distinct ones).

The product of its (nonzero) digits is 168, while the sum is 18.

The square root of 13271220 is about 3642.9685697244. The cubic root of 13271220 is about 236.7574295354.

Adding to 13271220 its reverse (2217231), we get a palindrome (15488451).

The spelling of 13271220 in words is "thirteen million, two hundred seventy-one thousand, two hundred twenty".