27601991 has 2 divisors, whose sum is σ = 27601992. Its totient is φ = 27601990.

The previous prime is 27601969. The next prime is 27601993. The reversal of 27601991 is 19910672.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 27601991 - 2²² = 23407687 is a prime.

Together with 27601993, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27601993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13800995 + 13800996.

It is an arithmetic number, because the mean of its divisors is an integer number (13800996).

Almost surely, 2^27601991 is an apocalyptic number.

27601991 is a deficient number, since it is larger than the sum of its proper divisors (1).

27601991 is an equidigital number, since it uses as much as digits as its factorization.

27601991 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6804, while the sum is 35.

The square root of 27601991 is about 5253.7597013948. The cubic root of 27601991 is about 302.2132282132.

The spelling of 27601991 in words is "twenty-seven million, six hundred one thousand, nine hundred ninety-one".