677795021 has 2 divisors, whose sum is σ = 677795022. Its totient is φ = 677795020.

The previous prime is 677795011. The next prime is 677795023. The reversal of 677795021 is 120597776.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 670033225 + 7761796 = 25885^2 + 2786^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-677795021 is a prime.

Together with 677795023, 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 (677795023) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 338897510 + 338897511.

It is an arithmetic number, because the mean of its divisors is an integer number (338897511).

Almost surely, 2^677795021 is an apocalyptic number.

It is an amenable number.

677795021 is a deficient number, since it is larger than the sum of its proper divisors (1).

677795021 is an equidigital number, since it uses as much as digits as its factorization.

677795021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 185220, while the sum is 44.

The square root of 677795021 is about 26034.4967495053. The cubic root of 677795021 is about 878.4144231594.

The spelling of 677795021 in words is "six hundred seventy-seven million, seven hundred ninety-five thousand, twenty-one".