20864972 has 6 divisors (see below), whose sum is σ = 36513708. Its totient is φ = 10432484.

The previous prime is 20864947. The next prime is 20864981. The reversal of 20864972 is 27946802.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2608118 + ... + 2608125.

It is an arithmetic number, because the mean of its divisors is an integer number (6085618).

Almost surely, 2^20864972 is an apocalyptic number.

It is an amenable number.

20864972 is a deficient number, since it is larger than the sum of its proper divisors (15648736).

20864972 is a wasteful number, since it uses less digits than its factorization.

20864972 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5216247 (or 5216245 counting only the distinct ones).

The product of its (nonzero) digits is 48384, while the sum is 38.

The square root of 20864972 is about 4567.8191733036. The cubic root of 20864972 is about 275.2998250562.

The spelling of 20864972 in words is "twenty million, eight hundred sixty-four thousand, nine hundred seventy-two".