21656034 has 24 divisors (see below), whose sum is σ = 47567052. Its totient is φ = 7119360.

The previous prime is 21656023. The next prime is 21656039. The reversal of 21656034 is 43065612.

21656034 is a `hidden beast` number, since 2 + 1 + 656 + 0 + 3 + 4 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 21650409 + 5625 = 4653^2 + 75^2 .

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21655989 and 21656007.

It is not an unprimeable number, because it can be changed into a prime (21656039) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6927 + ... + 9554.

Almost surely, 2^21656034 is an apocalyptic number.

21656034 is an abundant number, since it is smaller than the sum of its proper divisors (25911018).

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

21656034 is a wasteful number, since it uses less digits than its factorization.

21656034 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16562 (or 16559 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 21656034 is about 4653.6044094873. The cubic root of 21656034 is about 278.7359431737.

The spelling of 21656034 in words is "twenty-one million, six hundred fifty-six thousand, thirty-four".