321908612172 has 96 divisors (see below), whose sum is σ = 910251965952. Its totient is φ = 86436658176.

The previous prime is 321908612171. The next prime is 321908612197. The reversal of 321908612172 is 271216809123.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (321908612171) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 810298 + ... + 1140350.

It is an arithmetic number, because the mean of its divisors is an integer number (9481791312).

Almost surely, 2^321908612172 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 321908612172, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (455125982976).

321908612172 is an abundant number, since it is smaller than the sum of its proper divisors (588343353780).

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

321908612172 is a wasteful number, since it uses less digits than its factorization.

321908612172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 330767 (or 330765 counting only the distinct ones).

The product of its (nonzero) digits is 72576, while the sum is 42.

The spelling of 321908612172 in words is "three hundred twenty-one billion, nine hundred eight million, six hundred twelve thousand, one hundred seventy-two".