686837519051904 has 512 divisors, whose sum is σ = 2276105259859200. Its totient is φ = 202067907379200.

The previous prime is 686837519051903. The next prime is 686837519051923. The reversal of 686837519051904 is 409150915738686.

686837519051904 is a `hidden beast` number, since 6 + 8 + 68 + 37 + 5 + 19 + 0 + 519 + 0 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is not an unprimeable number, because it can be changed into a prime (686837519051903) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 647909304 + ... + 648968520.

Almost surely, 2^{686837519051904} is an apocalyptic number.

686837519051904 is a gapful number since it is divisible by the number (64) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686837519051904, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1138052629929600).

686837519051904 is an abundant number, since it is smaller than the sum of its proper divisors (1589267740807296).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

686837519051904 is a wasteful number, since it uses less digits than its factorization.

686837519051904 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1059749 (or 1059731 counting only the distinct ones).

The product of its (nonzero) digits is 391910400, while the sum is 72.

The spelling of 686837519051904 in words is "six hundred eighty-six trillion, eight hundred thirty-seven billion, five hundred nineteen million, fifty-one thousand, nine hundred four".