21838572 has 60 divisors (see below), whose sum is σ = 65252880. Its totient is φ = 6238944.

The previous prime is 21838567. The next prime is 21838603. The reversal of 21838572 is 27583812.

21838572 is a `hidden beast` number, since 2 + 1 + 83 + 8 + 572 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 2547 + ... + 7082.

It is an arithmetic number, because the mean of its divisors is an integer number (1087548).

Almost surely, 2^21838572 is an apocalyptic number.

It is an amenable number.

21838572 is an abundant number, since it is smaller than the sum of its proper divisors (43414308).

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

21838572 is a wasteful number, since it uses less digits than its factorization.

21838572 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9652 (or 9641 counting only the distinct ones).

The product of its digits is 26880, while the sum is 36.

The square root of 21838572 is about 4673.1757938259. The cubic root of 21838572 is about 279.5169050721.

The spelling of 21838572 in words is "twenty-one million, eight hundred thirty-eight thousand, five hundred seventy-two".