27921391 has 2 divisors, whose sum is σ = 27921392. Its totient is φ = 27921390.

The previous prime is 27921373. The next prime is 27921409. The reversal of 27921391 is 19312972.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (27921373) and next prime (27921409).

It is a cyclic number.

It is not a de Polignac number, because 27921391 - 2⁷ = 27921263 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (27921371) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13960695 + 13960696.

It is an arithmetic number, because the mean of its divisors is an integer number (13960696).

Almost surely, 2^27921391 is an apocalyptic number.

27921391 is a deficient number, since it is larger than the sum of its proper divisors (1).

27921391 is an equidigital number, since it uses as much as digits as its factorization.

27921391 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6804, while the sum is 34.

The square root of 27921391 is about 5284.0695491259. The cubic root of 27921391 is about 303.3744603362.

The spelling of 27921391 in words is "twenty-seven million, nine hundred twenty-one thousand, three hundred ninety-one".