645454316644 has 12 divisors (see below), whose sum is σ = 1130020268524. Its totient is φ = 322591382784.

The previous prime is 645454316627. The next prime is 645454316723. The reversal of 645454316644 is 446613454546.

It can be written as a sum of positive squares in 2 ways, for example, as 122421612544 + 523032704100 = 349888^2 + 723210^2 .

It is a super-2 number, since 2×645454316644² (a number of 24 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 645454316591 and 645454316600.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33933189 + ... + 33952204.

Almost surely, 2^645454316644 is an apocalyptic number.

It is an amenable number.

645454316644 is a deficient number, since it is larger than the sum of its proper divisors (484565951880).

645454316644 is a wasteful number, since it uses less digits than its factorization.

645454316644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 67887774 (or 67887772 counting only the distinct ones).

The product of its digits is 16588800, while the sum is 52.

The spelling of 645454316644 in words is "six hundred forty-five billion, four hundred fifty-four million, three hundred sixteen thousand, six hundred forty-four".