18172069 has 4 divisors (see below), whose sum is σ = 18663244. Its totient is φ = 17680896.

The previous prime is 18172019. The next prime is 18172073. The reversal of 18172069 is 96027181.

It is a happy number.

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

It can be written as a sum of positive squares in 2 ways, for example, as 11730625 + 6441444 = 3425^2 + 2538^2 .

It is a cyclic number.

It is not a de Polignac number, because 18172069 - 2⁹ = 18171557 is a prime.

It is a super-2 number, since 2×18172069² = 660448183481522, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18172019) 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, 245532 + ... + 245605.

It is an arithmetic number, because the mean of its divisors is an integer number (4665811).

Almost surely, 2^18172069 is an apocalyptic number.

It is an amenable number.

18172069 is a deficient number, since it is larger than the sum of its proper divisors (491175).

18172069 is an equidigital number, since it uses as much as digits as its factorization.

18172069 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 491174.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 18172069 is about 4262.8709809235. The cubic root of 18172069 is about 262.9065820203.

The spelling of 18172069 in words is "eighteen million, one hundred seventy-two thousand, sixty-nine".