18181429 has 4 divisors (see below), whose sum is σ = 20778784. Its totient is φ = 15584076.

The previous prime is 18181421. The next prime is 18181439. The reversal of 18181429 is 92418181.

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: 92418181 = 139 ⋅664879.

It is a cyclic number.

It is not a de Polignac number, because 18181429 - 2³ = 18181421 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 18181394 and 18181403.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18181421) 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, 1298667 + ... + 1298680.

It is an arithmetic number, because the mean of its divisors is an integer number (5194696).

Almost surely, 2^18181429 is an apocalyptic number.

It is an amenable number.

18181429 is a deficient number, since it is larger than the sum of its proper divisors (2597355).

18181429 is an equidigital number, since it uses as much as digits as its factorization.

18181429 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2597354.

The product of its digits is 4608, while the sum is 34.

The square root of 18181429 is about 4263.9686912547. The cubic root of 18181429 is about 262.9517132457.

The spelling of 18181429 in words is "eighteen million, one hundred eighty-one thousand, four hundred twenty-nine".