685701172187 has 2 divisors, whose sum is σ = 685701172188. Its totient is φ = 685701172186.

The previous prime is 685701172133. The next prime is 685701172193. The reversal of 685701172187 is 781271107586.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 685701172187 - 2²⁰ = 685700123611 is a prime.

It is not a weakly prime, because it can be changed into another prime (685701102187) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 342850586093 + 342850586094.

It is an arithmetic number, because the mean of its divisors is an integer number (342850586094).

Almost surely, 2^685701172187 is an apocalyptic number.

685701172187 is a deficient number, since it is larger than the sum of its proper divisors (1).

685701172187 is an equidigital number, since it uses as much as digits as its factorization.

685701172187 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1317120, while the sum is 53.

The spelling of 685701172187 in words is "six hundred eighty-five billion, seven hundred one million, one hundred seventy-two thousand, one hundred eighty-seven".