21852728 has 8 divisors (see below), whose sum is σ = 40973880. Its totient is φ = 10926360.

The previous prime is 21852683. The next prime is 21852749. The reversal of 21852728 is 82725812.

It is a tau number, because it is divible by the number of its divisors (8).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1365788 + ... + 1365803.

It is an arithmetic number, because the mean of its divisors is an integer number (5121735).

Almost surely, 2^21852728 is an apocalyptic number.

It is an amenable number.

21852728 is a deficient number, since it is larger than the sum of its proper divisors (19121152).

21852728 is a wasteful number, since it uses less digits than its factorization.

21852728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2731597 (or 2731593 counting only the distinct ones).

The product of its digits is 17920, while the sum is 35.

The square root of 21852728 is about 4674.6901501597. The cubic root of 21852728 is about 279.5772873269.

It can be divided in two parts, 2185 and 2728, that added together give a cube (4913 = 17³).

The spelling of 21852728 in words is "twenty-one million, eight hundred fifty-two thousand, seven hundred twenty-eight".