21486856 has 16 divisors (see below), whose sum is σ = 40971600. Its totient is φ = 10561104.

The previous prime is 21486821. The next prime is 21486859. The reversal of 21486856 is 65868412.

It is not an unprimeable number, because it can be changed into a prime (21486859) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 22290 + ... + 23233.

It is an arithmetic number, because the mean of its divisors is an integer number (2560725).

Almost surely, 2^21486856 is an apocalyptic number.

It is an amenable number.

21486856 is a deficient number, since it is larger than the sum of its proper divisors (19484744).

21486856 is a wasteful number, since it uses less digits than its factorization.

21486856 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 45588 (or 45584 counting only the distinct ones).

The product of its digits is 92160, while the sum is 40.

The square root of 21486856 is about 4635.3916770862. The cubic root of 21486856 is about 278.0082118928.

The spelling of 21486856 in words is "twenty-one million, four hundred eighty-six thousand, eight hundred fifty-six".