677721617 has 2 divisors, whose sum is σ = 677721618. Its totient is φ = 677721616.

The previous prime is 677721553. The next prime is 677721647. The reversal of 677721617 is 716127776.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 673973521 + 3748096 = 25961^2 + 1936^2 .

It is a cyclic number.

It is not a de Polignac number, because 677721617 - 2⁶ = 677721553 is a prime.

It is not a weakly prime, because it can be changed into another prime (677721647) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 338860808 + 338860809.

It is an arithmetic number, because the mean of its divisors is an integer number (338860809).

Almost surely, 2^677721617 is an apocalyptic number.

It is an amenable number.

677721617 is a deficient number, since it is larger than the sum of its proper divisors (1).

677721617 is an equidigital number, since it uses as much as digits as its factorization.

677721617 is an evil number, because the sum of its binary digits is even.

The product of its digits is 172872, while the sum is 44.

The square root of 677721617 is about 26033.0869663972. The cubic root of 677721617 is about 878.3827117726.

The spelling of 677721617 in words is "six hundred seventy-seven million, seven hundred twenty-one thousand, six hundred seventeen".