645637230 has 120 divisors (see below), whose sum is σ = 2019607128. Its totient is φ = 147565152.

The previous prime is 645637189. The next prime is 645637241. The reversal of 645637230 is 32736546.

645637230 is a `hidden beast` number, since 64 + 563 + 7 + 2 + 30 = 666.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 59 ways as a sum of consecutive naturals, for example, 31557 + ... + 47823.

Almost surely, 2^645637230 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 645637230, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1009803564).

645637230 is an abundant number, since it is smaller than the sum of its proper divisors (1373969898).

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

645637230 is a wasteful number, since it uses less digits than its factorization.

645637230 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 16300 (or 16284 counting only the distinct ones).

The product of its (nonzero) digits is 90720, while the sum is 36.

The square root of 645637230 is about 25409.3925547228. The cubic root of 645637230 is about 864.2967007622.

The spelling of 645637230 in words is "six hundred forty-five million, six hundred thirty-seven thousand, two hundred thirty".