645237040434 has 24 divisors (see below), whose sum is σ = 1501163727408. Its totient is φ = 184353440040.

The previous prime is 645237040417. The next prime is 645237040439. The reversal of 645237040434 is 434040732546.

It is a Harshad number since it is a multiple of its sum of digits (42).

It is not an unprimeable number, because it can be changed into a prime (645237040439) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1097341612 + ... + 1097342199.

It is an arithmetic number, because the mean of its divisors is an integer number (62548488642).

Almost surely, 2^645237040434 is an apocalyptic number.

645237040434 is an abundant number, since it is smaller than the sum of its proper divisors (855926686974).

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

645237040434 is a wasteful number, since it uses less digits than its factorization.

645237040434 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2194683830 (or 2194683823 counting only the distinct ones).

The product of its (nonzero) digits is 967680, while the sum is 42.

The spelling of 645237040434 in words is "six hundred forty-five billion, two hundred thirty-seven million, forty thousand, four hundred thirty-four".