645846677816 has 32 divisors (see below), whose sum is σ = 1303215227280. Its totient is φ = 298945420800.

The previous prime is 645846677779. The next prime is 645846677887. The reversal of 645846677816 is 618776648546.

It is a Harshad number since it is a multiple of its sum of digits (68).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 38916890 + ... + 38933481.

Almost surely, 2^645846677816 is an apocalyptic number.

It is an amenable number.

645846677816 is an abundant number, since it is smaller than the sum of its proper divisors (657368549464).

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

645846677816 is a wasteful number, since it uses less digits than its factorization.

645846677816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 77850455 (or 77850451 counting only the distinct ones).

The product of its digits is 325140480, while the sum is 68.

The spelling of 645846677816 in words is "six hundred forty-five billion, eight hundred forty-six million, six hundred seventy-seven thousand, eight hundred sixteen".