687800797 has 2 divisors, whose sum is σ = 687800798. Its totient is φ = 687800796.

The previous prime is 687800783. The next prime is 687800843. The reversal of 687800797 is 797008786.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 351225081 + 336575716 = 18741^2 + 18346^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-687800797 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687800747) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343900398 + 343900399.

It is an arithmetic number, because the mean of its divisors is an integer number (343900399).

Almost surely, 2^687800797 is an apocalyptic number.

It is an amenable number.

687800797 is a deficient number, since it is larger than the sum of its proper divisors (1).

687800797 is an equidigital number, since it uses as much as digits as its factorization.

687800797 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1185408, while the sum is 52.

The square root of 687800797 is about 26225.9565507152. The cubic root of 687800797 is about 882.7157824200.

The spelling of 687800797 in words is "six hundred eighty-seven million, eight hundred thousand, seven hundred ninety-seven".