18993903165 has 16 divisors (see below), whose sum is σ = 33766939200. Its totient is φ = 10130081616.

The previous prime is 18993903161. The next prime is 18993903209. The reversal of 18993903165 is 56130939981.

18993903165 is a `hidden beast` number, since 1 + 8 + 99 + 390 + 3 + 165 = 666.

It is not a de Polignac number, because 18993903165 - 2² = 18993903161 is a prime.

It is a hoax number, since the sum of its digits (54) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18993903161) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 70347655 + ... + 70347924.

It is an arithmetic number, because the mean of its divisors is an integer number (2110433700).

Almost surely, 2^18993903165 is an apocalyptic number.

18993903165 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18993903165 is a deficient number, since it is larger than the sum of its proper divisors (14773036035).

18993903165 is a wasteful number, since it uses less digits than its factorization.

18993903165 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 140695593 (or 140695587 counting only the distinct ones).

The product of its (nonzero) digits is 1574640, while the sum is 54.

The spelling of 18993903165 in words is "eighteen billion, nine hundred ninety-three million, nine hundred three thousand, one hundred sixty-five".