27138691 has 2 divisors, whose sum is σ = 27138692. Its totient is φ = 27138690.

The previous prime is 27138667. The next prime is 27138697. The reversal of 27138691 is 19683172.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27138691 - 2⁵ = 27138659 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 27138691.

It is not a weakly prime, because it can be changed into another prime (27138697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13569345 + 13569346.

It is an arithmetic number, because the mean of its divisors is an integer number (13569346).

Almost surely, 2^27138691 is an apocalyptic number.

27138691 is a deficient number, since it is larger than the sum of its proper divisors (1).

27138691 is an equidigital number, since it uses as much as digits as its factorization.

27138691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 18144, while the sum is 37.

The square root of 27138691 is about 5209.4808762486. The cubic root of 27138691 is about 300.5127933476.

The spelling of 27138691 in words is "twenty-seven million, one hundred thirty-eight thousand, six hundred ninety-one".