645110051664 has 80 divisors (see below), whose sum is σ = 1838503203264. Its totient is φ = 193654041600.

The previous prime is 645110051657. The next prime is 645110051681. The reversal of 645110051664 is 466150011546.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12582102 + ... + 12633269.

Almost surely, 2^645110051664 is an apocalyptic number.

It is an amenable number.

645110051664 is an abundant number, since it is smaller than the sum of its proper divisors (1193393151600).

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

645110051664 is a wasteful number, since it uses less digits than its factorization.

645110051664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 25215436 (or 25215430 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 39.

The spelling of 645110051664 in words is "six hundred forty-five billion, one hundred ten million, fifty-one thousand, six hundred sixty-four".