645203861670 has 32 divisors (see below), whose sum is σ = 1556512542432. Its totient is φ = 171162888192.

The previous prime is 645203861669. The next prime is 645203861683. The reversal of 645203861670 is 76168302546.

It is a super-2 number, since 2×645203861670² (a number of 24 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (48) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax 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 15 ways as a sum of consecutive naturals, for example, 55711297 + ... + 55722876.

It is an arithmetic number, because the mean of its divisors is an integer number (48641016951).

Almost surely, 2^645203861670 is an apocalyptic number.

645203861670 is an abundant number, since it is smaller than the sum of its proper divisors (911308680762).

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

645203861670 is a wasteful number, since it uses less digits than its factorization.

645203861670 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111434376.

The product of its (nonzero) digits is 1451520, while the sum is 48.

The spelling of 645203861670 in words is "six hundred forty-five billion, two hundred three million, eight hundred sixty-one thousand, six hundred seventy".