1990108566864 has 120 divisors (see below), whose sum is σ = 6271857456384. Its totient is φ = 583609536000.

The previous prime is 1990108566839. The next prime is 1990108566877. The reversal of 1990108566864 is 4686658010991.

1990108566864 is a `hidden beast` number, since 1 + 9 + 9 + 0 + 1 + 0 + 8 + 566 + 8 + 64 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 20215117 + ... + 20313324.

Almost surely, 2^{1990108566864} is an apocalyptic number.

It is an amenable number.

1990108566864 is an abundant number, since it is smaller than the sum of its proper divisors (4281748889520).

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

1990108566864 is a wasteful number, since it uses less digits than its factorization.

1990108566864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40528497 (or 40528488 counting only the distinct ones).

The product of its (nonzero) digits is 22394880, while the sum is 63.

The spelling of 1990108566864 in words is "one trillion, nine hundred ninety billion, one hundred eight million, five hundred sixty-six thousand, eight hundred sixty-four".