21742504 has 16 divisors (see below), whose sum is σ = 46591200. Its totient is φ = 9318192.

The previous prime is 21742493. The next prime is 21742571. The reversal of 21742504 is 40524712.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194074 + ... + 194185.

It is an arithmetic number, because the mean of its divisors is an integer number (2911950).

Almost surely, 2^21742504 is an apocalyptic number.

It is an amenable number.

21742504 is an abundant number, since it is smaller than the sum of its proper divisors (24848696).

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

21742504 is a wasteful number, since it uses less digits than its factorization.

21742504 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 388272 (or 388268 counting only the distinct ones).

The product of its (nonzero) digits is 2240, while the sum is 25.

The square root of 21742504 is about 4662.8858017327. The cubic root of 21742504 is about 279.1064371241.

The spelling of 21742504 in words is "twenty-one million, seven hundred forty-two thousand, five hundred four".