19131891968 has 36 divisors (see below), whose sum is σ = 43644632640. Its totient is φ = 8199381504.

The previous prime is 19131891967. The next prime is 19131891979. The reversal of 19131891968 is 86919813191.

It is a Harshad number since it is a multiple of its sum of digits (56).

It is not an unprimeable number, because it can be changed into a prime (19131891967) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 5336348 + ... + 5339931.

Almost surely, 2^19131891968 is an apocalyptic number.

It is an amenable number.

19131891968 is an abundant number, since it is smaller than the sum of its proper divisors (24512740672).

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

19131891968 is an equidigital number, since it uses as much as digits as its factorization.

19131891968 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10676302 (or 10676288 counting only the distinct ones).

The product of its digits is 839808, while the sum is 56.

The spelling of 19131891968 in words is "nineteen billion, one hundred thirty-one million, eight hundred ninety-one thousand, nine hundred sixty-eight".