18131929 has 4 divisors (see below), whose sum is σ = 18252160. Its totient is φ = 18011700.

The previous prime is 18131921. The next prime is 18131933. The reversal of 18131929 is 92913181.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 92913181 = 373 ⋅249097.

It is a cyclic number.

It is not a de Polignac number, because 18131929 - 2³ = 18131921 is a prime.

It is a super-2 number, since 2×18131929² = 657533698522082, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18131894 and 18131903.

It is not an unprimeable number, because it can be changed into a prime (18131921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 59889 + ... + 60190.

It is an arithmetic number, because the mean of its divisors is an integer number (4563040).

Almost surely, 2^18131929 is an apocalyptic number.

It is an amenable number.

18131929 is a deficient number, since it is larger than the sum of its proper divisors (120231).

18131929 is a wasteful number, since it uses less digits than its factorization.

18131929 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 120230.

The product of its digits is 3888, while the sum is 34.

The square root of 18131929 is about 4258.1602835027. The cubic root of 18131929 is about 262.7128625650.

The spelling of 18131929 in words is "eighteen million, one hundred thirty-one thousand, nine hundred twenty-nine".