687655079 has 2 divisors, whose sum is σ = 687655080. Its totient is φ = 687655078.

The previous prime is 687655069. The next prime is 687655099. The reversal of 687655079 is 970556786.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 687655079 - 2²⁴ = 670877863 is a prime.

It is a Sophie Germain prime.

It is a self number, because there is not a number n which added to its sum of digits gives 687655079.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687655009) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343827539 + 343827540.

It is an arithmetic number, because the mean of its divisors is an integer number (343827540).

Almost surely, 2^687655079 is an apocalyptic number.

687655079 is a deficient number, since it is larger than the sum of its proper divisors (1).

687655079 is an equidigital number, since it uses as much as digits as its factorization.

687655079 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3175200, while the sum is 53.

The square root of 687655079 is about 26223.1782780044. The cubic root of 687655079 is about 882.6534404048.

The spelling of 687655079 in words is "six hundred eighty-seven million, six hundred fifty-five thousand, seventy-nine".