645631626040 has 16 divisors (see below), whose sum is σ = 1452671158680. Its totient is φ = 258252650400.

The previous prime is 645631625999. The next prime is 645631626077. The reversal of 645631626040 is 40626136546.

It is a congruent number.

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, 8070395286 + ... + 8070395365.

Almost surely, 2^645631626040 is an apocalyptic number.

It is an amenable number.

645631626040 is an abundant number, since it is smaller than the sum of its proper divisors (807039532640).

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

645631626040 is a wasteful number, since it uses less digits than its factorization.

645631626040 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16140790662 (or 16140790658 counting only the distinct ones).

The product of its (nonzero) digits is 622080, while the sum is 43.

The spelling of 645631626040 in words is "six hundred forty-five billion, six hundred thirty-one million, six hundred twenty-six thousand, forty".