17981905112 has 8 divisors (see below), whose sum is σ = 33716072100. Its totient is φ = 8990952552.

The previous prime is 17981905111. The next prime is 17981905133. The reversal of 17981905112 is 21150918971.

It is a tau number, because it is divible by the number of its divisors (8).

It is a super-2 number, since 2×17981905112² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (17981905111) 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 as a sum of consecutive naturals, namely, 1123869062 + ... + 1123869077.

Almost surely, 2^17981905112 is an apocalyptic number.

It is an amenable number.

17981905112 is a deficient number, since it is larger than the sum of its proper divisors (15734166988).

17981905112 is a wasteful number, since it uses less digits than its factorization.

17981905112 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2247738145 (or 2247738141 counting only the distinct ones).

The product of its (nonzero) digits is 45360, while the sum is 44.

The spelling of 17981905112 in words is "seventeen billion, nine hundred eighty-one million, nine hundred five thousand, one hundred twelve".