19901009912 has 64 divisors (see below), whose sum is σ = 43760217600. Its totient is φ = 8307089280.

The previous prime is 19901009903. The next prime is 19901009977. The reversal of 19901009912 is 21990010991.

It is a happy number.

It is a hoax number, since the sum of its digits (41) coincides with the sum of the digits of its distinct prime factors.

It is a self number, because there is not a number n which added to its sum of digits gives 19901009912.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 852962 + ... + 875982.

It is an arithmetic number, because the mean of its divisors is an integer number (683753400).

Almost surely, 2^19901009912 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19901009912, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21880108800).

19901009912 is an abundant number, since it is smaller than the sum of its proper divisors (23859207688).

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

19901009912 is a wasteful number, since it uses less digits than its factorization.

19901009912 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23436 (or 23432 counting only the distinct ones).

The product of its (nonzero) digits is 13122, while the sum is 41.

The spelling of 19901009912 in words is "nineteen billion, nine hundred one million, nine thousand, nine hundred twelve".