19779290100 has 144 divisors (see below), whose sum is σ = 64353589440. Its totient is φ = 5210870400.

The previous prime is 19779290099. The next prime is 19779290137. The reversal of 19779290100 is 109297791.

19779290100 is a `hidden beast` number, since 197 + 79 + 290 + 100 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 179970 + ... + 268230.

Almost surely, 2^19779290100 is an apocalyptic number.

19779290100 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 19779290100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (32176794720).

19779290100 is an abundant number, since it is smaller than the sum of its proper divisors (44574299340).

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

19779290100 is a wasteful number, since it uses less digits than its factorization.

19779290100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 88367 (or 88354 counting only the distinct ones).

The product of its (nonzero) digits is 71442, while the sum is 45.

The spelling of 19779290100 in words is "nineteen billion, seven hundred seventy-nine million, two hundred ninety thousand, one hundred".