27642761 has 2 divisors, whose sum is σ = 27642762. Its totient is φ = 27642760.

The previous prime is 27642749. The next prime is 27642763. The reversal of 27642761 is 16724672.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 14969161 + 12673600 = 3869^2 + 3560^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-27642761 is a prime.

Together with 27642763, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (27642763) 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 as a sum of consecutive naturals, namely, 13821380 + 13821381.

It is an arithmetic number, because the mean of its divisors is an integer number (13821381).

Almost surely, 2^27642761 is an apocalyptic number.

It is an amenable number.

27642761 is a deficient number, since it is larger than the sum of its proper divisors (1).

27642761 is an equidigital number, since it uses as much as digits as its factorization.

27642761 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 28224, while the sum is 35.

The square root of 27642761 is about 5257.6383481559. The cubic root of 27642761 is about 302.3619514443.

The spelling of 27642761 in words is "twenty-seven million, six hundred forty-two thousand, seven hundred sixty-one".