19909124478 has 12 divisors (see below), whose sum is σ = 43136436408. Its totient is φ = 6636374820.

The previous prime is 19909124449. The next prime is 19909124479. The reversal of 19909124478 is 87442190991.

19909124478 is a `hidden beast` number, since 199 + 0 + 9 + 1 + 2 + 447 + 8 = 666.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19909124479) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 553031218 + ... + 553031253.

It is an arithmetic number, because the mean of its divisors is an integer number (3594703034).

Almost surely, 2^19909124478 is an apocalyptic number.

19909124478 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

19909124478 is an abundant number, since it is smaller than the sum of its proper divisors (23227311930).

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

19909124478 is a wasteful number, since it uses less digits than its factorization.

19909124478 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1106062479 (or 1106062476 counting only the distinct ones).

The product of its (nonzero) digits is 1306368, while the sum is 54.

The spelling of 19909124478 in words is "nineteen billion, nine hundred nine million, one hundred twenty-four thousand, four hundred seventy-eight".