13157720 has 64 divisors (see below), whose sum is σ = 31026240. Its totient is φ = 5017600.

The previous prime is 13157701. The next prime is 13157723. The reversal of 13157720 is 2775131.

13157720 = T₁₉ + T₂₀ + ... + T₄₂₈.

13157720 = 395² + 396² + ... + 465².

It is a self number, because there is not a number n which added to its sum of digits gives 13157720.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (13157723) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 116384 + ... + 116496.

It is an arithmetic number, because the mean of its divisors is an integer number (484785).

Almost surely, 2^13157720 is an apocalyptic number.

13157720 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 13157720, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (15513120).

13157720 is an abundant number, since it is smaller than the sum of its proper divisors (17868520).

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

13157720 is a wasteful number, since it uses less digits than its factorization.

13157720 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236 (or 232 counting only the distinct ones).

The product of its (nonzero) digits is 1470, while the sum is 26.

The square root of 13157720 is about 3627.3571646586. The cubic root of 13157720 is about 236.0805527952.

The spelling of 13157720 in words is "thirteen million, one hundred fifty-seven thousand, seven hundred twenty".