1989120621024 has 72 divisors (see below), whose sum is σ = 5866064076600. Its totient is φ = 663040204416.

The previous prime is 1989120621017. The next prime is 1989120621043. The reversal of 1989120621024 is 4201260219891.

It is a happy number.

1989120621024 is a `hidden beast` number, since 1 + 9 + 8 + 9 + 12 + 0 + 621 + 0 + 2 + 4 = 666.

It is a tau number, because it is divible by the number of its divisors (72).

It is a hoax number, since the sum of its digits (45) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 127893499 + ... + 127909050.

It is an arithmetic number, because the mean of its divisors is an integer number (81473112175).

Almost surely, 2^{1989120621024} is an apocalyptic number.

It is an amenable number.

1989120621024 is an abundant number, since it is smaller than the sum of its proper divisors (3876943455576).

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

1989120621024 is an equidigital number, since it uses as much as digits as its factorization.

1989120621024 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 255802574 (or 255802554 counting only the distinct ones).

The product of its (nonzero) digits is 124416, while the sum is 45.

The spelling of 1989120621024 in words is "one trillion, nine hundred eighty-nine billion, one hundred twenty million, six hundred twenty-one thousand, twenty-four".