687139812739 has 2 divisors, whose sum is σ = 687139812740. Its totient is φ = 687139812738.

The previous prime is 687139812661. The next prime is 687139812781. The reversal of 687139812739 is 937218931786.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 687139812739 - 2¹⁵ = 687139779971 is a prime.

It is a super-2 number, since 2×687139812739² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (687139812839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 343569906369 + 343569906370.

It is an arithmetic number, because the mean of its divisors is an integer number (343569906370).

Almost surely, 2^687139812739 is an apocalyptic number.

687139812739 is a deficient number, since it is larger than the sum of its proper divisors (1).

687139812739 is an equidigital number, since it uses as much as digits as its factorization.

687139812739 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 27433728, while the sum is 64.

The spelling of 687139812739 in words is "six hundred eighty-seven billion, one hundred thirty-nine million, eight hundred twelve thousand, seven hundred thirty-nine".