677843021 has 2 divisors, whose sum is σ = 677843022. Its totient is φ = 677843020.

The previous prime is 677843011. The next prime is 677843027. The reversal of 677843021 is 120348776.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 468722500 + 209120521 = 21650^2 + 14461^2 .

It is a cyclic number.

It is not a de Polignac number, because 677843021 - 2¹⁸ = 677580877 is a prime.

It is a super-2 number, since 2×677843021² = 918942322236812882, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (677843027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 338921510 + 338921511.

It is an arithmetic number, because the mean of its divisors is an integer number (338921511).

Almost surely, 2^677843021 is an apocalyptic number.

It is an amenable number.

677843021 is a deficient number, since it is larger than the sum of its proper divisors (1).

677843021 is an equidigital number, since it uses as much as digits as its factorization.

677843021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 56448, while the sum is 38.

The square root of 677843021 is about 26035.4185869941. The cubic root of 677843021 is about 878.4351584829.

The spelling of 677843021 in words is "six hundred seventy-seven million, eight hundred forty-three thousand, twenty-one".