17999911231 has 4 divisors (see below), whose sum is σ = 18947275000. Its totient is φ = 17052547464.

The previous prime is 17999911141. The next prime is 17999911249. The reversal of 17999911231 is 13211999971.

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 17999911231 - 2¹¹ = 17999909183 is a prime.

It is a super-2 number, since 2×17999911231² (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 (17999911291) 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 in 3 ways as a sum of consecutive naturals, for example, 473681856 + ... + 473681893.

It is an arithmetic number, because the mean of its divisors is an integer number (4736818750).

Almost surely, 2^17999911231 is an apocalyptic number.

17999911231 is a deficient number, since it is larger than the sum of its proper divisors (947363769).

17999911231 is an equidigital number, since it uses as much as digits as its factorization.

17999911231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 947363768.

The product of its digits is 275562, while the sum is 52.

The spelling of 17999911231 in words is "seventeen billion, nine hundred ninety-nine million, nine hundred eleven thousand, two hundred thirty-one".