645275392 has 72 divisors (see below), whose sum is σ = 1384777296. Its totient is φ = 298991616.

The previous prime is 645275387. The next prime is 645275399. The reversal of 645275392 is 293572546.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645275399) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 290478 + ... + 292690.

It is an arithmetic number, because the mean of its divisors is an integer number (19233018).

Almost surely, 2^645275392 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 645275392, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (692388648).

645275392 is an abundant number, since it is smaller than the sum of its proper divisors (739501904).

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

645275392 is a wasteful number, since it uses less digits than its factorization.

645275392 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2313 (or 2299 counting only the distinct ones).

The product of its digits is 453600, while the sum is 43.

The square root of 645275392 is about 25402.2713945033. The cubic root of 645275392 is about 864.1352097495.

The spelling of 645275392 in words is "six hundred forty-five million, two hundred seventy-five thousand, three hundred ninety-two".