18166942831 has 4 divisors (see below), whose sum is σ = 18278396632. Its totient is φ = 18055489032.

The previous prime is 18166942813. The next prime is 18166942837. The reversal of 18166942831 is 13824966181.

It is a happy number.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18166942831 - 2¹¹ = 18166940783 is a prime.

It is a super-2 number, since 2×18166942831² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18166942837) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 55726656 + ... + 55726981.

It is an arithmetic number, because the mean of its divisors is an integer number (4569599158).

Almost surely, 2^18166942831 is an apocalyptic number.

18166942831 is a deficient number, since it is larger than the sum of its proper divisors (111453801).

18166942831 is a wasteful number, since it uses less digits than its factorization.

18166942831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111453800.

The product of its digits is 497664, while the sum is 49.

The spelling of 18166942831 in words is "eighteen billion, one hundred sixty-six million, nine hundred forty-two thousand, eight hundred thirty-one".