645631116 has 72 divisors (see below), whose sum is σ = 1647531312. Its totient is φ = 195619200.

The previous prime is 645631099. The next prime is 645631157. The reversal of 645631116 is 611136546.

645631116 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 785986 + ... + 786806.

Almost surely, 2^645631116 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 645631116, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (823765656).

645631116 is an abundant number, since it is smaller than the sum of its proper divisors (1001900196).

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

645631116 is a wasteful number, since it uses less digits than its factorization.

645631116 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 983 (or 910 counting only the distinct ones).

The product of its digits is 12960, while the sum is 33.

The square root of 645631116 is about 25409.2722445961. The cubic root of 645631116 is about 864.2939725394.

The spelling of 645631116 in words is "six hundred forty-five million, six hundred thirty-one thousand, one hundred sixteen".