645025750680 has 512 divisors, whose sum is σ = 2141798400000. Its totient is φ = 154785945600.

The previous prime is 645025750657. The next prime is 645025750693. The reversal of 645025750680 is 86057520546.

It is a happy number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1848211146 + ... + 1848211494.

It is an arithmetic number, because the mean of its divisors is an integer number (4183200000).

Almost surely, 2^645025750680 is an apocalyptic number.

645025750680 is a gapful number since it is divisible by the number (60) 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 645025750680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1070899200000).

645025750680 is an abundant number, since it is smaller than the sum of its proper divisors (1496772649320).

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

645025750680 is a wasteful number, since it uses less digits than its factorization.

645025750680 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 823 (or 819 counting only the distinct ones).

The product of its (nonzero) digits is 2016000, while the sum is 48.

The spelling of 645025750680 in words is "six hundred forty-five billion, twenty-five million, seven hundred fifty thousand, six hundred eighty".