685970731 has 2 divisors, whose sum is σ = 685970732. Its totient is φ = 685970730.

The previous prime is 685970651. The next prime is 685970783. The reversal of 685970731 is 137079586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685970731 - 2⁷ = 685970603 is a prime.

It is a super-2 number, since 2×685970731² = 941111687577348722, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (685970531) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342985365 + 342985366.

It is an arithmetic number, because the mean of its divisors is an integer number (342985366).

Almost surely, 2^685970731 is an apocalyptic number.

685970731 is a deficient number, since it is larger than the sum of its proper divisors (1).

685970731 is an equidigital number, since it uses as much as digits as its factorization.

685970731 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 317520, while the sum is 46.

The square root of 685970731 is about 26191.0429536512. The cubic root of 685970731 is about 881.9321916769.

The spelling of 685970731 in words is "six hundred eighty-five million, nine hundred seventy thousand, seven hundred thirty-one".