17939991468 has 96 divisors (see below), whose sum is σ = 48826552320. Its totient is φ = 5020637760.

The previous prime is 17939991457. The next prime is 17939991469. The reversal of 17939991468 is 86419993971.

It is a junction number, because it is equal to n+sod(n) for n = 17939991399 and 17939991408.

It is not an unprimeable number, because it can be changed into a prime (17939991469) 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 31 ways as a sum of consecutive naturals, for example, 1396153 + ... + 1408943.

It is an arithmetic number, because the mean of its divisors is an integer number (508609920).

Almost surely, 2^17939991468 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 17939991468, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24413276160).

17939991468 is an abundant number, since it is smaller than the sum of its proper divisors (30886560852).

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

17939991468 is a wasteful number, since it uses less digits than its factorization.

17939991468 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13147 (or 13145 counting only the distinct ones).

The product of its digits is 26453952, while the sum is 66.

The spelling of 17939991468 in words is "seventeen billion, nine hundred thirty-nine million, nine hundred ninety-one thousand, four hundred sixty-eight".