18115429 has 4 divisors (see below), whose sum is σ = 18302284. Its totient is φ = 17928576.

The previous prime is 18115403. The next prime is 18115441. The reversal of 18115429 is 92451181.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 92451181 = 571 ⋅161911.

It can be written as a sum of positive squares in 2 ways, for example, as 8567329 + 9548100 = 2927^2 + 3090^2 .

It is a cyclic number.

It is not a de Polignac number, because 18115429 - 2¹³ = 18107237 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18115429.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18115469) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 93282 + ... + 93475.

It is an arithmetic number, because the mean of its divisors is an integer number (4575571).

Almost surely, 2^18115429 is an apocalyptic number.

It is an amenable number.

18115429 is a deficient number, since it is larger than the sum of its proper divisors (186855).

18115429 is an equidigital number, since it uses as much as digits as its factorization.

18115429 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 186854.

The product of its digits is 2880, while the sum is 31.

The square root of 18115429 is about 4256.2223861072. Note that the first 3 decimals coincide. The cubic root of 18115429 is about 262.6331490796.

The spelling of 18115429 in words is "eighteen million, one hundred fifteen thousand, four hundred twenty-nine".