27921539 has 2 divisors, whose sum is σ = 27921540. Its totient is φ = 27921538.

The previous prime is 27921529. The next prime is 27921541. The reversal of 27921539 is 93512972.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27921539 is a prime.

It is a super-2 number, since 2×27921539² = 1559224680257042, which contains 22 as substring.

Together with 27921541, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1736867 and since 27921539 and 1736867 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (27921529) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13960769 + 13960770.

It is an arithmetic number, because the mean of its divisors is an integer number (13960770).

Almost surely, 2^27921539 is an apocalyptic number.

27921539 is a deficient number, since it is larger than the sum of its proper divisors (1).

27921539 is an equidigital number, since it uses as much as digits as its factorization.

27921539 is an evil number, because the sum of its binary digits is even.

The product of its digits is 34020, while the sum is 38.

The square root of 27921539 is about 5284.0835534651. The cubic root of 27921539 is about 303.3749963570.

The spelling of 27921539 in words is "twenty-seven million, nine hundred twenty-one thousand, five hundred thirty-nine".