21364929 has 12 divisors (see below), whose sum is σ = 31179876. Its totient is φ = 14095872.

The previous prime is 21364919. The next prime is 21364939. The reversal of 21364929 is 92946312.

21364929 is a `hidden beast` number, since 2 + 1 + 3 + 649 + 2 + 9 = 666.

It is an interprime number because it is at equal distance from previous prime (21364919) and next prime (21364939).

It can be written as a sum of positive squares in 2 ways, for example, as 13395600 + 7969329 = 3660^2 + 2823^2 .

It is not a de Polignac number, because 21364929 - 2⁵ = 21364897 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21364893 and 21364902.

It is not an unprimeable number, because it can be changed into a prime (21364919) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 11364 + ... + 13109.

It is an arithmetic number, because the mean of its divisors is an integer number (2598323).

Almost surely, 2^21364929 is an apocalyptic number.

It is an amenable number.

21364929 is a deficient number, since it is larger than the sum of its proper divisors (9814947).

21364929 is a wasteful number, since it uses less digits than its factorization.

21364929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24576 (or 24573 counting only the distinct ones).

The product of its digits is 23328, while the sum is 36.

The square root of 21364929 is about 4622.2212192841. The cubic root of 21364929 is about 277.4813622740.

The spelling of 21364929 in words is "twenty-one million, three hundred sixty-four thousand, nine hundred twenty-nine".