17991978060 has 192 divisors, whose sum is σ = 59230209024. Its totient is φ = 3995827200.

The previous prime is 17991978013. The next prime is 17991978089. The reversal of 17991978060 is 6087919971.

It is a super-3 number, since 3×17991978060³ (a number of 32 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 2122230 + ... + 2130690.

It is an arithmetic number, because the mean of its divisors is an integer number (308490672).

Almost surely, 2^17991978060 is an apocalyptic number.

17991978060 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 17991978060, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29615104512).

17991978060 is an abundant number, since it is smaller than the sum of its proper divisors (41238230964).

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

17991978060 is a wasteful number, since it uses less digits than its factorization.

17991978060 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8624 (or 8622 counting only the distinct ones).

The product of its (nonzero) digits is 1714608, while the sum is 57.

The spelling of 17991978060 in words is "seventeen billion, nine hundred ninety-one million, nine hundred seventy-eight thousand, sixty".