21713672 has 32 divisors (see below), whose sum is σ = 42259800. Its totient is φ = 10450944.

The previous prime is 21713669. The next prime is 21713677. The reversal of 21713672 is 27631712.

It can be written as a sum of positive squares in 4 ways, for example, as 21215236 + 498436 = 4606^2 + 706^2 .

It is not an unprimeable number, because it can be changed into a prime (21713677) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 31928 + ... + 32600.

Almost surely, 2^21713672 is an apocalyptic number.

It is an amenable number.

21713672 is a deficient number, since it is larger than the sum of its proper divisors (20546128).

21713672 is a wasteful number, since it uses less digits than its factorization.

21713672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 825 (or 821 counting only the distinct ones).

The product of its digits is 3528, while the sum is 29.

The square root of 21713672 is about 4659.7931284554. The cubic root of 21713672 is about 278.9830113455.

The spelling of 21713672 in words is "twenty-one million, seven hundred thirteen thousand, six hundred seventy-two".