645133604031 has 18 divisors (see below), whose sum is σ = 1084000002072. Its totient is φ = 368647773480.

The previous prime is 645133603969. The next prime is 645133604039. The reversal of 645133604031 is 130406331546.

645133604031 is a `hidden beast` number, since 6 + 4 + 5 + 13 + 3 + 604 + 0 + 31 = 666.

It is not a de Polignac number, because 645133604031 - 2⁷ = 645133603903 is a prime.

It is a super-2 number, since 2×645133604031² (a number of 24 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (645133604039) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 17 ways as a sum of consecutive naturals, for example, 731443555 + ... + 731444436.

Almost surely, 2^645133604031 is an apocalyptic number.

645133604031 is a deficient number, since it is larger than the sum of its proper divisors (438866398041).

645133604031 is a wasteful number, since it uses less digits than its factorization.

645133604031 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1462888011 (or 1462888001 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 36.

Adding to 645133604031 its reverse (130406331546), we get a palindrome (775539935577).

The spelling of 645133604031 in words is "six hundred forty-five billion, one hundred thirty-three million, six hundred four thousand, thirty-one".