19991912772 has 192 divisors, whose sum is σ = 53551038464. Its totient is φ = 5761082880.

The previous prime is 19991912771. The next prime is 19991912797. The reversal of 19991912772 is 27721919991.

It is not an unprimeable number, because it can be changed into a prime (19991912771) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 26409018 + ... + 26409774.

Almost surely, 2^19991912772 is an apocalyptic number.

19991912772 is a gapful number since it is divisible by the number (12) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 19991912772, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26775519232).

19991912772 is an abundant number, since it is smaller than the sum of its proper divisors (33559125692).

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

19991912772 is a wasteful number, since it uses less digits than its factorization.

19991912772 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 978 (or 976 counting only the distinct ones).

The product of its digits is 1285956, while the sum is 57.

The spelling of 19991912772 in words is "nineteen billion, nine hundred ninety-one million, nine hundred twelve thousand, seven hundred seventy-two".