21039672 has 16 divisors (see below), whose sum is σ = 52599240. Its totient is φ = 7013216.

The previous prime is 21039671. The next prime is 21039677. The reversal of 21039672 is 27693012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21039671) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 438303 + ... + 438350.

Almost surely, 2^21039672 is an apocalyptic number.

It is an amenable number.

21039672 is an abundant number, since it is smaller than the sum of its proper divisors (31559568).

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

21039672 is a wasteful number, since it uses less digits than its factorization.

21039672 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 876662 (or 876658 counting only the distinct ones).

The product of its (nonzero) digits is 4536, while the sum is 30.

The square root of 21039672 is about 4586.9022226335. The cubic root of 21039672 is about 276.0660417471.

The spelling of 21039672 in words is "twenty-one million, thirty-nine thousand, six hundred seventy-two".