645353140 has 12 divisors (see below), whose sum is σ = 1355241636. Its totient is φ = 258141248.

The previous prime is 645353129. The next prime is 645353141. The reversal of 645353140 is 41353546.

It can be written as a sum of positive squares in 2 ways, for example, as 83283876 + 562069264 = 9126^2 + 23708^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645353141) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 16133809 + ... + 16133848.

It is an arithmetic number, because the mean of its divisors is an integer number (112936803).

Almost surely, 2^645353140 is an apocalyptic number.

It is an amenable number.

645353140 is an abundant number, since it is smaller than the sum of its proper divisors (709888496).

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

645353140 is a wasteful number, since it uses less digits than its factorization.

645353140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 32267666 (or 32267664 counting only the distinct ones).

The product of its (nonzero) digits is 21600, while the sum is 31.

The square root of 645353140 is about 25403.8016840000. The cubic root of 645353140 is about 864.1699143562.

The spelling of 645353140 in words is "six hundred forty-five million, three hundred fifty-three thousand, one hundred forty".