21497352 has 64 divisors (see below), whose sum is σ = 56548800. Its totient is φ = 6800640.

The previous prime is 21497351. The next prime is 21497369. The reversal of 21497352 is 25379412.

It is a super-2 number, since 2×21497352² = 924272286023808, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21497351) 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, 46402 + ... + 46862.

It is an arithmetic number, because the mean of its divisors is an integer number (883575).

Almost surely, 2^21497352 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 21497352, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28274400).

21497352 is an abundant number, since it is smaller than the sum of its proper divisors (35051448).

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

21497352 is a wasteful number, since it uses less digits than its factorization.

21497352 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 566 (or 562 counting only the distinct ones).

The product of its digits is 15120, while the sum is 33.

The square root of 21497352 is about 4636.5236977719. The cubic root of 21497352 is about 278.0534721082.

The spelling of 21497352 in words is "twenty-one million, four hundred ninety-seven thousand, three hundred fifty-two".