684935131 has 2 divisors, whose sum is σ = 684935132. Its totient is φ = 684935130.

The previous prime is 684935099. The next prime is 684935143. The reversal of 684935131 is 131539486.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 684935131 - 2⁵ = 684935099 is a prime.

It is a super-2 number, since 2×684935131² = 938272267355974322, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (684930131) 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, 342467565 + 342467566.

It is an arithmetic number, because the mean of its divisors is an integer number (342467566).

Almost surely, 2^684935131 is an apocalyptic number.

684935131 is a deficient number, since it is larger than the sum of its proper divisors (1).

684935131 is an equidigital number, since it uses as much as digits as its factorization.

684935131 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 77760, while the sum is 40.

The square root of 684935131 is about 26171.2653687207. The cubic root of 684935131 is about 881.4881547642.

The spelling of 684935131 in words is "six hundred eighty-four million, nine hundred thirty-five thousand, one hundred thirty-one".