19999772100 has 288 divisors, whose sum is σ = 80161536000. Its totient is φ = 4155753600.

The previous prime is 19999772099. The next prime is 19999772119. The reversal of 19999772100 is 127799991.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 159801 + ... + 255999.

Almost surely, 2^19999772100 is an apocalyptic number.

19999772100 is a gapful number since it is divisible by the number (10) 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 19999772100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40080768000).

19999772100 is an abundant number, since it is smaller than the sum of its proper divisors (60161763900).

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

19999772100 is a wasteful number, since it uses less digits than its factorization.

19999772100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 96240 (or 96227 counting only the distinct ones).

The product of its (nonzero) digits is 642978, while the sum is 54.

The spelling of 19999772100 in words is "nineteen billion, nine hundred ninety-nine million, seven hundred seventy-two thousand, one hundred".