21457896 has 32 divisors (see below), whose sum is σ = 55978560. Its totient is φ = 6841472.

The previous prime is 21457871. The next prime is 21457939. The reversal of 21457896 is 69875412.

It is a congruent number.

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, 18885 + ... + 19988.

It is an arithmetic number, because the mean of its divisors is an integer number (1749330).

Almost surely, 2^21457896 is an apocalyptic number.

It is an amenable number.

21457896 is an abundant number, since it is smaller than the sum of its proper divisors (34520664).

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

21457896 is a wasteful number, since it uses less digits than its factorization.

21457896 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 38905 (or 38901 counting only the distinct ones).

The product of its digits is 120960, while the sum is 42.

The square root of 21457896 is about 4632.2668316927. The cubic root of 21457896 is about 277.8832558479.

The spelling of 21457896 in words is "twenty-one million, four hundred fifty-seven thousand, eight hundred ninety-six".