21373056 has 48 divisors (see below), whose sum is σ = 61506510. Its totient is φ = 7123968.

The previous prime is 21372991. The next prime is 21373061. The reversal of 21373056 is 65037312.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 21013056 + 360000 = 4584^2 + 600^2 .

It is a tau number, because it is divible by the number of its divisors (48).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

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, 8125 + ... + 10428.

Almost surely, 2^21373056 is an apocalyptic number.

It is an amenable number.

21373056 is an abundant number, since it is smaller than the sum of its proper divisors (40133454).

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

21373056 is a wasteful number, since it uses less digits than its factorization.

21373056 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18573 (or 18558 counting only the distinct ones).

The product of its (nonzero) digits is 3780, while the sum is 27.

The square root of 21373056 is about 4623.1002584846. The cubic root of 21373056 is about 277.5165415024.

The spelling of 21373056 in words is "twenty-one million, three hundred seventy-three thousand, fifty-six".