19912779936 has 480 divisors, whose sum is σ = 70302859200. Its totient is φ = 5476584960.

The previous prime is 19912779923. The next prime is 19912779941. The reversal of 19912779936 is 63997721991.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a nude number because it is divisible by every one of its digits.

It is an unprimeable number.

It is a polite number, since it can be written in 79 ways as a sum of consecutive naturals, for example, 60159291 + ... + 60159621.

It is an arithmetic number, because the mean of its divisors is an integer number (146464290).

Almost surely, 2^19912779936 is an apocalyptic number.

19912779936 is a gapful number since it is divisible by the number (16) 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 19912779936, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35151429600).

19912779936 is an abundant number, since it is smaller than the sum of its proper divisors (50390079264).

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

19912779936 is an equidigital number, since it uses as much as digits as its factorization.

19912779936 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407 (or 372 counting only the distinct ones).

The product of its digits is 11573604, while the sum is 63.

The spelling of 19912779936 in words is "nineteen billion, nine hundred twelve million, seven hundred seventy-nine thousand, nine hundred thirty-six".