21366942 has 16 divisors (see below), whose sum is σ = 43215120. Its totient is φ = 7042112.

The previous prime is 21366913. The next prime is 21366971. The reversal of 21366942 is 24966312.

It is an interprime number because it is at equal distance from previous prime (21366913) and next prime (21366971).

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, 19473 + ... + 20540.

It is an arithmetic number, because the mean of its divisors is an integer number (2700945).

Almost surely, 2^21366942 is an apocalyptic number.

21366942 is an abundant number, since it is smaller than the sum of its proper divisors (21848178).

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

21366942 is a wasteful number, since it uses less digits than its factorization.

21366942 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40107.

The product of its digits is 15552, while the sum is 33.

The square root of 21366942 is about 4622.4389666063. The cubic root of 21366942 is about 277.4900767493.

The spelling of 21366942 in words is "twenty-one million, three hundred sixty-six thousand, nine hundred forty-two".