18172842 has 8 divisors (see below), whose sum is σ = 36345696. Its totient is φ = 6057612.

The previous prime is 18172837. The next prime is 18172849. The reversal of 18172842 is 24827181.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

18172842 is an admirable number.

It is a Smith number, since the sum of its digits (33) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (18172849) 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, 1514398 + ... + 1514409.

It is an arithmetic number, because the mean of its divisors is an integer number (4543212).

Almost surely, 2^18172842 is an apocalyptic number.

18172842 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18172842 is a wasteful number, since it uses less digits than its factorization.

18172842 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3028812.

The product of its digits is 7168, while the sum is 33.

The square root of 18172842 is about 4262.9616465551. The cubic root of 18172842 is about 262.9103097907.

The spelling of 18172842 in words is "eighteen million, one hundred seventy-two thousand, eight hundred forty-two".