18155229 has 4 divisors (see below), whose sum is σ = 24206976. Its totient is φ = 12103484.

The previous prime is 18155209. The next prime is 18155231. The reversal of 18155229 is 92255181.

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.

It is a cyclic number.

It is not a de Polignac number, because 18155229 - 2⁸ = 18154973 is a prime.

It is a super-2 number, since 2×18155229² = 659224680084882, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18155229.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18155209) 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, 3025869 + ... + 3025874.

It is an arithmetic number, because the mean of its divisors is an integer number (6051744).

Almost surely, 2^18155229 is an apocalyptic number.

It is an amenable number.

18155229 is a deficient number, since it is larger than the sum of its proper divisors (6051747).

18155229 is an equidigital number, since it uses as much as digits as its factorization.

18155229 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6051746.

The product of its digits is 7200, while the sum is 33.

The square root of 18155229 is about 4260.8953284492. The cubic root of 18155229 is about 262.8253453497.

The spelling of 18155229 in words is "eighteen million, one hundred fifty-five thousand, two hundred twenty-nine".