687523391 has 2 divisors, whose sum is σ = 687523392. Its totient is φ = 687523390.

The previous prime is 687523373. The next prime is 687523411. The reversal of 687523391 is 193325786.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 687523391 - 2⁶ = 687523327 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (687523351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343761695 + 343761696.

It is an arithmetic number, because the mean of its divisors is an integer number (343761696).

Almost surely, 2^687523391 is an apocalyptic number.

687523391 is a deficient number, since it is larger than the sum of its proper divisors (1).

687523391 is an equidigital number, since it uses as much as digits as its factorization.

687523391 is an evil number, because the sum of its binary digits is even.

The product of its digits is 272160, while the sum is 44.

The square root of 687523391 is about 26220.6672493283. The cubic root of 687523391 is about 882.5970932184.

The spelling of 687523391 in words is "six hundred eighty-seven million, five hundred twenty-three thousand, three hundred ninety-one".