686646838445634 has 192 divisors, whose sum is σ = 1721588302137600. Its totient is φ = 195477914112000.

The previous prime is 686646838445587. The next prime is 686646838445657. The reversal of 686646838445634 is 436544838646686.

686646838445634 is a `hidden beast` number, since 6 + 8 + 6 + 6 + 4 + 6 + 8 + 3 + 8 + 44 + 563 + 4 = 666.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 15204398014 + ... + 15204443174.

It is an arithmetic number, because the mean of its divisors is an integer number (8966605740300).

Almost surely, 2^{686646838445634} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686646838445634, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (860794151068800).

686646838445634 is an abundant number, since it is smaller than the sum of its proper divisors (1034941463691966).

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

686646838445634 is a wasteful number, since it uses less digits than its factorization.

686646838445634 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53337 (or 53334 counting only the distinct ones).

The product of its digits is 45864714240, while the sum is 81.

The spelling of 686646838445634 in words is "six hundred eighty-six trillion, six hundred forty-six billion, eight hundred thirty-eight million, four hundred forty-five thousand, six hundred thirty-four".