877640689 has 2 divisors, whose sum is σ = 877640690. Its totient is φ = 877640688.

The previous prime is 877640671. The next prime is 877640779. The reversal of 877640689 is 986046778.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 877640625 + 64 = 29625^2 + 8^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-877640689 is a prime.

It is not a weakly prime, because it can be changed into another prime (877640639) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 438820344 + 438820345.

It is an arithmetic number, because the mean of its divisors is an integer number (438820345).

Almost surely, 2^877640689 is an apocalyptic number.

It is an amenable number.

877640689 is a deficient number, since it is larger than the sum of its proper divisors (1).

877640689 is an equidigital number, since it uses as much as digits as its factorization.

877640689 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4064256, while the sum is 55.

The square root of 877640689 is about 29625.0010801688. The cubic root of 877640689 is about 957.4268072314.

The spelling of 877640689 in words is "eight hundred seventy-seven million, six hundred forty thousand, six hundred eighty-nine".