686191964925 has 96 divisors (see below), whose sum is σ = 1235349504000. Its totient is φ = 334812614400.

The previous prime is 686191964921. The next prime is 686191964981. The reversal of 686191964925 is 529469191686.

It is not a de Polignac number, because 686191964925 - 2² = 686191964921 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (686191964921) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 21143611 + ... + 21176039.

It is an arithmetic number, because the mean of its divisors is an integer number (12868224000).

Almost surely, 2^686191964925 is an apocalyptic number.

It is an amenable number.

686191964925 is a deficient number, since it is larger than the sum of its proper divisors (549157539075).

686191964925 is a wasteful number, since it uses less digits than its factorization.

686191964925 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 32971 (or 32966 counting only the distinct ones).

The product of its digits is 50388480, while the sum is 66.

The spelling of 686191964925 in words is "six hundred eighty-six billion, one hundred ninety-one million, nine hundred sixty-four thousand, nine hundred twenty-five".