645246321632 has 96 divisors (see below), whose sum is σ = 1431532569600. Its totient is φ = 283631155200.

The previous prime is 645246321617. The next prime is 645246321653. The reversal of 645246321632 is 236123642546.

645246321632 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×645246321632² (a number of 24 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (44).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 15900344 + ... + 15940872.

It is an arithmetic number, because the mean of its divisors is an integer number (14911797600).

Almost surely, 2^645246321632 is an apocalyptic number.

645246321632 is a gapful number since it is divisible by the number (62) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645246321632, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (715766284800).

645246321632 is an abundant number, since it is smaller than the sum of its proper divisors (786286247968).

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

645246321632 is a wasteful number, since it uses less digits than its factorization.

645246321632 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42040 (or 42032 counting only the distinct ones).

The product of its digits is 1244160, while the sum is 44.

The spelling of 645246321632 in words is "six hundred forty-five billion, two hundred forty-six million, three hundred twenty-one thousand, six hundred thirty-two".