21679522 has 16 divisors (see below), whose sum is σ = 34999992. Its totient is φ = 10033920.

The previous prime is 21679477. The next prime is 21679561. The reversal of 21679522 is 22597612.

It can be written as a sum of positive squares in 4 ways, for example, as 20620681 + 1058841 = 4541^2 + 1029^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

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, 3153 + ... + 7300.

Almost surely, 2^21679522 is an apocalyptic number.

21679522 is a deficient number, since it is larger than the sum of its proper divisors (13320470).

21679522 is a wasteful number, since it uses less digits than its factorization.

21679522 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10533.

The product of its digits is 15120, while the sum is 34.

The square root of 21679522 is about 4656.1273608010. The cubic root of 21679522 is about 278.8366785212.

It can be divided in two parts, 21679 and 522, that added together give a square (22201 = 149²).

The spelling of 21679522 in words is "twenty-one million, six hundred seventy-nine thousand, five hundred twenty-two".