27973521 has 27 divisors (see below), whose sum is σ = 42401307. Its totient is φ = 17771040.

The previous prime is 27973513. The next prime is 27973531. The reversal of 27973521 is 12537972.

The square root of 27973521 is 5289.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1347921 + 26625600 = 1161^2 + 5160^2 .

It is not a de Polignac number, because 27973521 - 2³ = 27973513 is a prime.

It is not an unprimeable number, because it can be changed into a prime (27973511) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 650526 + ... + 650568.

Almost surely, 2^27973521 is an apocalyptic number.

27973521 is the 5289-th square number.

27973521 is the 2645-th centered octagonal number.

It is an amenable number.

27973521 is a deficient number, since it is larger than the sum of its proper divisors (14427786).

27973521 is an equidigital number, since it uses as much as digits as its factorization.

27973521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 174 (or 87 counting only the distinct ones).

The product of its digits is 26460, while the sum is 36.

The cubic root of 27973521 is about 303.5631457605.

Multiplying 27973521 by its sum of digits (36), we get a square (1007046756 = 31734²).

The spelling of 27973521 in words is "twenty-seven million, nine hundred seventy-three thousand, five hundred twenty-one".