27972621 has 20 divisors (see below), whose sum is σ = 42022332. Its totient is φ = 18543168.

The previous prime is 27972583. The next prime is 27972643. The reversal of 27972621 is 12627972.

27972621 is a `hidden beast` number, since 27 + 9 + 7 + 2 + 621 = 666.

It can be written as a sum of positive squares in 2 ways, for example, as 14356521 + 13616100 = 3789^2 + 3690^2 .

It is not a de Polignac number, because 27972621 - 2⁷ = 27972493 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27972671) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 15081 + ... + 16833.

Almost surely, 2^27972621 is an apocalyptic number.

It is an amenable number.

27972621 is a deficient number, since it is larger than the sum of its proper divisors (14049711).

27972621 is a wasteful number, since it uses less digits than its factorization.

27972621 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1962 (or 1953 counting only the distinct ones).

The product of its digits is 21168, while the sum is 36.

The square root of 27972621 is about 5288.9149170695. The cubic root of 27972621 is about 303.5598901846.

It can be divided in two parts, 279 and 72621, that added together give a square (72900 = 270²).

The spelling of 27972621 in words is "twenty-seven million, nine hundred seventy-two thousand, six hundred twenty-one".