21697192 has 32 divisors (see below), whose sum is σ = 44956800. Its totient is φ = 9734400.

The previous prime is 21697189. The next prime is 21697201. The reversal of 21697192 is 29179612.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5392 + ... + 8512.

It is an arithmetic number, because the mean of its divisors is an integer number (1404900).

Almost surely, 2^21697192 is an apocalyptic number.

21697192 is a gapful number since it is divisible by the number (22) 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 21697192, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22478400).

21697192 is an abundant number, since it is smaller than the sum of its proper divisors (23259608).

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

21697192 is a wasteful number, since it uses less digits than its factorization.

21697192 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3217 (or 3213 counting only the distinct ones).

The product of its digits is 13608, while the sum is 37.

The square root of 21697192 is about 4658.0244739589. The cubic root of 21697192 is about 278.9124136798.

The spelling of 21697192 in words is "twenty-one million, six hundred ninety-seven thousand, one hundred ninety-two".