21266946 has 24 divisors (see below), whose sum is σ = 47203884. Its totient is φ = 6915840.

The previous prime is 21266941. The next prime is 21266951. The reversal of 21266946 is 64966212.

It is an interprime number because it is at equal distance from previous prime (21266941) and next prime (21266951).

It can be written as a sum of positive squares in 2 ways, for example, as 21261321 + 5625 = 4611^2 + 75^2 .

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 21266946.

It is not an unprimeable number, because it can be changed into a prime (21266941) 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, 13671 + ... + 15146.

Almost surely, 2^21266946 is an apocalyptic number.

21266946 is an abundant number, since it is smaller than the sum of its proper divisors (25936938).

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

21266946 is a wasteful number, since it uses less digits than its factorization.

21266946 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28866 (or 28863 counting only the distinct ones).

The product of its digits is 31104, while the sum is 36.

The square root of 21266946 is about 4611.6099141189. The cubic root of 21266946 is about 277.0565207640.

The spelling of 21266946 in words is "twenty-one million, two hundred sixty-six thousand, nine hundred forty-six".