27977021 has 2 divisors, whose sum is σ = 27977022. Its totient is φ = 27977020.

The previous prime is 27977011. The next prime is 27977023. The reversal of 27977021 is 12077972.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27931225 + 45796 = 5285^2 + 214^2 .

It is a cyclic number.

It is not a de Polignac number, because 27977021 - 2¹⁴ = 27960637 is a prime.

Together with 27977023, 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 (27977023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 13988510 + 13988511.

It is an arithmetic number, because the mean of its divisors is an integer number (13988511).

Almost surely, 2^27977021 is an apocalyptic number.

It is an amenable number.

27977021 is a deficient number, since it is larger than the sum of its proper divisors (1).

27977021 is an equidigital number, since it uses as much as digits as its factorization.

27977021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12348, while the sum is 35.

The square root of 27977021 is about 5289.3308650528. The cubic root of 27977021 is about 303.5758056696.

The spelling of 27977021 in words is "twenty-seven million, nine hundred seventy-seven thousand, twenty-one".