19881489840 has 40 divisors (see below), whose sum is σ = 61632619248. Its totient is φ = 5301730560.

The previous prime is 19881489821. The next prime is 19881489877. The reversal of 19881489840 is 4898418891.

It is a tau number, because it is divible by the number of its divisors (40).

It is a Harshad number since it is a multiple of its sum of digits (60).

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, 41419531 + ... + 41420010.

Almost surely, 2^19881489840 is an apocalyptic number.

19881489840 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19881489840 is an abundant number, since it is smaller than the sum of its proper divisors (41751129408).

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

19881489840 is a wasteful number, since it uses less digits than its factorization.

19881489840 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82839557 (or 82839551 counting only the distinct ones).

The product of its (nonzero) digits is 5308416, while the sum is 60.

The spelling of 19881489840 in words is "nineteen billion, eight hundred eighty-one million, four hundred eighty-nine thousand, eight hundred forty".