645040034651 has 4 divisors (see below), whose sum is σ = 645676797792. Its totient is φ = 644403271512.

The previous prime is 645040034629. The next prime is 645040034719. The reversal of 645040034651 is 156430040546.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-645040034651 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (645040031651) 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, 318380051 + ... + 318382076.

It is an arithmetic number, because the mean of its divisors is an integer number (161419199448).

Almost surely, 2^645040034651 is an apocalyptic number.

645040034651 is a deficient number, since it is larger than the sum of its proper divisors (636763141).

645040034651 is a wasteful number, since it uses less digits than its factorization.

645040034651 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 636763140.

The product of its (nonzero) digits is 172800, while the sum is 38.

The spelling of 645040034651 in words is "six hundred forty-five billion, forty million, thirty-four thousand, six hundred fifty-one".