686737393650 has 1944 divisors, whose sum is σ = 2681877848832. Its totient is φ = 125139168000.

The previous prime is 686737393637. The next prime is 686737393687. The reversal of 686737393650 is 56393737686.

686737393650 is a `hidden beast` number, since 68 + 67 + 373 + 93 + 65 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is an unprimeable number.

It is a polite number, since it can be written in 971 ways as a sum of consecutive naturals, for example, 22152819135 + ... + 22152819165.

Almost surely, 2^686737393650 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 686737393650, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1340938924416).

686737393650 is an abundant number, since it is smaller than the sum of its proper divisors (1995140455182).

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

686737393650 is a wasteful number, since it uses less digits than its factorization.

686737393650 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 146 (or 101 counting only the distinct ones).

The product of its (nonzero) digits is 102876480, while the sum is 63.

The spelling of 686737393650 in words is "six hundred eighty-six billion, seven hundred thirty-seven million, three hundred ninety-three thousand, six hundred fifty".