18142805 has 4 divisors (see below), whose sum is σ = 21771372. Its totient is φ = 14514240.

The previous prime is 18142793. The next prime is 18142819. The reversal of 18142805 is 50824181.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 50824181 = 23 ⋅2209747.

It can be written as a sum of positive squares in 2 ways, for example, as 5340721 + 12802084 = 2311^2 + 3578^2 .

It is a de Polignac number, because none of the positive numbers 2^k-18142805 is a prime.

It is a super-2 number, since 2×18142805² = 658322746536050, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1814276 + ... + 1814285.

It is an arithmetic number, because the mean of its divisors is an integer number (5442843).

Almost surely, 2^18142805 is an apocalyptic number.

It is an amenable number.

18142805 is a deficient number, since it is larger than the sum of its proper divisors (3628567).

18142805 is an equidigital number, since it uses as much as digits as its factorization.

18142805 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3628566.

The product of its (nonzero) digits is 2560, while the sum is 29.

The square root of 18142805 is about 4259.4371693922. The cubic root of 18142805 is about 262.7653793894.

Adding to 18142805 its reverse (50824181), we get a palindrome (68966986).

It can be divided in two parts, 18142 and 805, that multiplied together give a triangular number (14604310 = T₅₄₀₄).

The spelling of 18142805 in words is "eighteen million, one hundred forty-two thousand, eight hundred five".