645074144131 has 4 divisors (see below), whose sum is σ = 645075779832. Its totient is φ = 645072508432.

The previous prime is 645074144123. The next prime is 645074144149. The reversal of 645074144131 is 131441470546.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 645074144131 - 2³ = 645074144123 is a prime.

It is a super-2 number, since 2×645074144131² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645074144831) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 177495 + ... + 1149631.

It is an arithmetic number, because the mean of its divisors is an integer number (161268944958).

Almost surely, 2^645074144131 is an apocalyptic number.

645074144131 is a deficient number, since it is larger than the sum of its proper divisors (1635701).

645074144131 is an equidigital number, since it uses as much as digits as its factorization.

645074144131 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1635700.

The product of its (nonzero) digits is 161280, while the sum is 40.

The spelling of 645074144131 in words is "six hundred forty-five billion, seventy-four million, one hundred forty-four thousand, one hundred thirty-one".