645111556000 has 48 divisors (see below), whose sum is σ = 1585039102920. Its totient is φ = 258044620800.

The previous prime is 645111555931. The next prime is 645111556021. The reversal of 645111556000 is 655111546.

It can be written as a sum of positive squares in 4 ways, for example, as 61776108304 + 583335447696 = 248548^2 + 763764^2 .

It is a super-2 number, since 2×645111556000² (a number of 24 digits) contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 80634945 + ... + 80642944.

Almost surely, 2^645111556000 is an apocalyptic number.

It is an amenable number.

645111556000 is an abundant number, since it is smaller than the sum of its proper divisors (939927546920).

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

645111556000 is a wasteful number, since it uses less digits than its factorization.

645111556000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161277914 (or 161277896 counting only the distinct ones).

The product of its (nonzero) digits is 18000, while the sum is 34.

Adding to 645111556000 its reverse (655111546), we get a palindrome (645766667546).

The spelling of 645111556000 in words is "six hundred forty-five billion, one hundred eleven million, five hundred fifty-six thousand".