18729899831 has 4 divisors (see below), whose sum is σ = 18752995464. Its totient is φ = 18706804200.

The previous prime is 18729899813. The next prime is 18729899849. The reversal of 18729899831 is 13899892781.

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

It is an interprime number because it is at equal distance from previous prime (18729899813) and next prime (18729899849).

It is a cyclic number.

It is not a de Polignac number, because 18729899831 - 2²⁶ = 18662790967 is a prime.

It is a super-2 number, since 2×18729899831² (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 (18729899801) 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, 11546600 + ... + 11548221.

It is an arithmetic number, because the mean of its divisors is an integer number (4688248866).

Almost surely, 2^18729899831 is an apocalyptic number.

18729899831 is a deficient number, since it is larger than the sum of its proper divisors (23095633).

18729899831 is an equidigital number, since it uses as much as digits as its factorization.

18729899831 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23095632.

The product of its digits is 15676416, while the sum is 65.

The spelling of 18729899831 in words is "eighteen billion, seven hundred twenty-nine million, eight hundred ninety-nine thousand, eight hundred thirty-one".