17916397987890 has 64 divisors (see below), whose sum is σ = 44503546613760. Its totient is φ = 4611387049920.

The previous prime is 17916397987853. The next prime is 17916397987919. The reversal of 17916397987890 is 9878979361971.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 25063024 + ... + 25767963.

It is an arithmetic number, because the mean of its divisors is an integer number (695367915840).

Almost surely, 2^{17916397987890} is an apocalyptic number.

17916397987890 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

17916397987890 is an abundant number, since it is smaller than the sum of its proper divisors (26587148625870).

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

17916397987890 is a wasteful number, since it uses less digits than its factorization.

17916397987890 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50831407.

The product of its (nonzero) digits is 2592487296, while the sum is 84.

The spelling of 17916397987890 in words is "seventeen trillion, nine hundred sixteen billion, three hundred ninety-seven million, nine hundred eighty-seven thousand, eight hundred ninety".