646820681232 has 160 divisors (see below), whose sum is σ = 1867031502336. Its totient is φ = 191265177600.

The previous prime is 646820681207. The next prime is 646820681251. The reversal of 646820681232 is 232186028646.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 24757008 + ... + 24783120.

Almost surely, 2^646820681232 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 646820681232, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (933515751168).

646820681232 is an abundant number, since it is smaller than the sum of its proper divisors (1220210821104).

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

646820681232 is a wasteful number, since it uses less digits than its factorization.

646820681232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27269 (or 27263 counting only the distinct ones).

The product of its (nonzero) digits is 1327104, while the sum is 48.

The spelling of 646820681232 in words is "six hundred forty-six billion, eight hundred twenty million, six hundred eighty-one thousand, two hundred thirty-two".