27979917 has 16 divisors (see below), whose sum is σ = 43677312. Its totient is φ = 15598080.

The previous prime is 27979901. The next prime is 27979933. The reversal of 27979917 is 71997972.

It is an interprime number because it is at equal distance from previous prime (27979901) and next prime (27979933).

It is not a de Polignac number, because 27979917 - 2⁴ = 27979901 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27979917.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27979957) 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 15 ways as a sum of consecutive naturals, for example, 15388 + ... + 17109.

It is an arithmetic number, because the mean of its divisors is an integer number (2729832).

Almost surely, 2^27979917 is an apocalyptic number.

It is an amenable number.

27979917 is a deficient number, since it is larger than the sum of its proper divisors (15697395).

27979917 is a wasteful number, since it uses less digits than its factorization.

27979917 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32548.

The product of its digits is 500094, while the sum is 51.

The square root of 27979917 is about 5289.6046166042. The cubic root of 27979917 is about 303.5862800419.

The spelling of 27979917 in words is "twenty-seven million, nine hundred seventy-nine thousand, nine hundred seventeen".