21157032 has 128 divisors (see below), whose sum is σ = 62092800. Its totient is φ = 5951232.

The previous prime is 21156953. The next prime is 21157039. The reversal of 21157032 is 23075112.

It is not an unprimeable number, because it can be changed into a prime (21157039) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 254863 + ... + 254945.

It is an arithmetic number, because the mean of its divisors is an integer number (485100).

Almost surely, 2^21157032 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 21157032, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31046400).

21157032 is an abundant number, since it is smaller than the sum of its proper divisors (40935768).

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

21157032 is a wasteful number, since it uses less digits than its factorization.

21157032 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 167 (or 163 counting only the distinct ones).

The product of its (nonzero) digits is 420, while the sum is 21.

The square root of 21157032 is about 4599.6773799909. The cubic root of 21157032 is about 276.5783921858.

The spelling of 21157032 in words is "twenty-one million, one hundred fifty-seven thousand, thirty-two".