21959712 has 36 divisors (see below), whose sum is σ = 62448750. Its totient is φ = 7319808.

The previous prime is 21959689. The next prime is 21959761. The reversal of 21959712 is 21795912.

It can be written as a sum of positive squares in only one way, i.e., 17943696 + 4016016 = 4236^2 + 2004^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is a super-2 number, since 2×21959712² = 964457902245888, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 37837 + ... + 38412.

Almost surely, 2^21959712 is an apocalyptic number.

It is an amenable number.

21959712 is an abundant number, since it is smaller than the sum of its proper divisors (40489038).

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

21959712 is a wasteful number, since it uses less digits than its factorization.

21959712 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 76265 (or 76254 counting only the distinct ones).

The product of its digits is 11340, while the sum is 36.

The square root of 21959712 is about 4686.1190765921. The cubic root of 21959712 is about 280.0327852767.

The spelling of 21959712 in words is "twenty-one million, nine hundred fifty-nine thousand, seven hundred twelve".