685993907 has 2 divisors, whose sum is σ = 685993908. Its totient is φ = 685993906.

The previous prime is 685993901. The next prime is 685993961. The reversal of 685993907 is 709399586.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 685993907 - 2¹⁸ = 685731763 is a prime.

It is a super-2 number, since 2×685993907² = 941175280882249298, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (685993901) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342996953 + 342996954.

It is an arithmetic number, because the mean of its divisors is an integer number (342996954).

Almost surely, 2^685993907 is an apocalyptic number.

685993907 is a deficient number, since it is larger than the sum of its proper divisors (1).

685993907 is an equidigital number, since it uses as much as digits as its factorization.

685993907 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 3674160, while the sum is 56.

The square root of 685993907 is about 26191.4853912488. The cubic root of 685993907 is about 881.9421237966.

The spelling of 685993907 in words is "six hundred eighty-five million, nine hundred ninety-three thousand, nine hundred seven".