19779814100 has 18 divisors (see below), whose sum is σ = 42922196814. Its totient is φ = 7911925600.

The previous prime is 19779814099. The next prime is 19779814129. The reversal of 19779814100 is 141897791.

It can be written as a sum of positive squares in 3 ways, for example, as 6283415824 + 13496398276 = 79268^2 + 116174^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 98898971 + ... + 98899170.

Almost surely, 2^19779814100 is an apocalyptic number.

19779814100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19779814100 is an abundant number, since it is smaller than the sum of its proper divisors (23142382714).

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

19779814100 is a wasteful number, since it uses less digits than its factorization.

19779814100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 197798155 (or 197798148 counting only the distinct ones).

The product of its (nonzero) digits is 127008, while the sum is 47.

The spelling of 19779814100 in words is "nineteen billion, seven hundred seventy-nine million, eight hundred fourteen thousand, one hundred".