1664699578944 has 56 divisors (see below), whose sum is σ = 4523558672448. Its totient is φ = 539902563840.

The previous prime is 1664699578889. The next prime is 1664699578961. The reversal of 1664699578944 is 4498759964661.

It is a self number, because there is not a number n which added to its sum of digits gives 1664699578944.

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, 117159252 + ... + 117173459.

Almost surely, 2^{1664699578944} is an apocalyptic number.

It is an amenable number.

1664699578944 is an abundant number, since it is smaller than the sum of its proper divisors (2858859093504).

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

1664699578944 is a wasteful number, since it uses less digits than its factorization.

1664699578944 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 234332763 (or 234332753 counting only the distinct ones).

The product of its digits is 2821754880, while the sum is 78.

The spelling of 1664699578944 in words is "one trillion, six hundred sixty-four billion, six hundred ninety-nine million, five hundred seventy-eight thousand, nine hundred forty-four".