20221272 has 64 divisors (see below), whose sum is σ = 56592000. Its totient is φ = 6689952.

The previous prime is 20221261. The next prime is 20221273. The reversal of 20221272 is 27212202.

It is a happy number.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20221273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 38403 + ... + 38925.

It is an arithmetic number, because the mean of its divisors is an integer number (884250).

Almost surely, 2^20221272 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20221272, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28296000).

20221272 is an abundant number, since it is smaller than the sum of its proper divisors (36370728).

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

20221272 is a wasteful number, since it uses less digits than its factorization.

20221272 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 717 (or 707 counting only the distinct ones).

The product of its (nonzero) digits is 224, while the sum is 18.

The square root of 20221272 is about 4496.8068671003. The cubic root of 20221272 is about 272.4391335033.

Adding to 20221272 its reverse (27212202), we get a palindrome (47433474).

The spelling of 20221272 in words is "twenty million, two hundred twenty-one thousand, two hundred seventy-two".