27921357 has 6 divisors (see below), whose sum is σ = 40330862. Its totient is φ = 18614232.

The previous prime is 27921281. The next prime is 27921367. The reversal of 27921357 is 75312972.

It can be written as a sum of positive squares in only one way, i.e., 18224361 + 9696996 = 4269^2 + 3114^2 .

It is a de Polignac number, because none of the positive numbers 2^k-27921357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27921367) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1551178 + ... + 1551195.

Almost surely, 2^27921357 is an apocalyptic number.

It is an amenable number.

27921357 is a deficient number, since it is larger than the sum of its proper divisors (12409505).

27921357 is a wasteful number, since it uses less digits than its factorization.

27921357 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3102379 (or 3102376 counting only the distinct ones).

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

The square root of 27921357 is about 5284.0663319077. The cubic root of 27921357 is about 303.3743371960.

The spelling of 27921357 in words is "twenty-seven million, nine hundred twenty-one thousand, three hundred fifty-seven".