19668172890 has 32 divisors (see below), whose sum is σ = 48726314496. Its totient is φ = 5075657280.

The previous prime is 19668172889. The next prime is 19668172903. The reversal of 19668172890 is 9827186691.

It is a self number, because there is not a number n which added to its sum of digits gives 19668172890.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10573357 + ... + 10575216.

It is an arithmetic number, because the mean of its divisors is an integer number (1522697328).

Almost surely, 2^19668172890 is an apocalyptic number.

19668172890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19668172890 is an abundant number, since it is smaller than the sum of its proper divisors (29058141606).

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

19668172890 is a wasteful number, since it uses less digits than its factorization.

19668172890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21148614.

The product of its (nonzero) digits is 2612736, while the sum is 57.

The spelling of 19668172890 in words is "nineteen billion, six hundred sixty-eight million, one hundred seventy-two thousand, eight hundred ninety".