21235956 has 48 divisors (see below), whose sum is σ = 56918400. Its totient is φ = 6036480.

The previous prime is 21235933. The next prime is 21235979. The reversal of 21235956 is 65953212.

It is an interprime number because it is at equal distance from previous prime (21235933) and next prime (21235979).

It is a hoax number, since the sum of its digits (33) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 19720 + ... + 20768.

It is an arithmetic number, because the mean of its divisors is an integer number (1185800).

Almost surely, 2^21235956 is an apocalyptic number.

It is an amenable number.

21235956 is an abundant number, since it is smaller than the sum of its proper divisors (35682444).

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

21235956 is a wasteful number, since it uses less digits than its factorization.

21235956 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1304 (or 1302 counting only the distinct ones).

The product of its digits is 16200, while the sum is 33.

The square root of 21235956 is about 4608.2486912058. The cubic root of 21235956 is about 276.9218805979.

It can be divided in two parts, 21 and 235956, that multiplied together give a square (4955076 = 2226²).

The spelling of 21235956 in words is "twenty-one million, two hundred thirty-five thousand, nine hundred fifty-six".