19943172390 has 32 divisors (see below), whose sum is σ = 47867339520. Its totient is φ = 5317765344.

The previous prime is 19943172377. The next prime is 19943172391. The reversal of 19943172390 is 9327134991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19943172391) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 697557 + ... + 725583.

It is an arithmetic number, because the mean of its divisors is an integer number (1495854360).

Almost surely, 2^19943172390 is an apocalyptic number.

19943172390 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19943172390 is an abundant number, since it is smaller than the sum of its proper divisors (27924167130).

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

19943172390 is a wasteful number, since it uses less digits than its factorization.

19943172390 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51756.

The product of its (nonzero) digits is 367416, while the sum is 48.

The spelling of 19943172390 in words is "nineteen billion, nine hundred forty-three million, one hundred seventy-two thousand, three hundred ninety".