18078142 has 4 divisors (see below), whose sum is σ = 27117216. Its totient is φ = 9039070.

The previous prime is 18078121. The next prime is 18078149. The reversal of 18078142 is 24187081.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 24187081 = 163 ⋅148387.

It is a super-3 number, since 3×18078142³ (a number of 23 digits) contains 333 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18078149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4519534 + ... + 4519537.

It is an arithmetic number, because the mean of its divisors is an integer number (6779304).

Almost surely, 2^18078142 is an apocalyptic number.

18078142 is a deficient number, since it is larger than the sum of its proper divisors (9039074).

18078142 is an equidigital number, since it uses as much as digits as its factorization.

18078142 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9039073.

The product of its (nonzero) digits is 3584, while the sum is 31.

The square root of 18078142 is about 4251.8398370588. The cubic root of 18078142 is about 262.4528326439.

The spelling of 18078142 in words is "eighteen million, seventy-eight thousand, one hundred forty-two".