18142021 has 2 divisors, whose sum is σ = 18142022. Its totient is φ = 18142020.

The previous prime is 18141997. The next prime is 18142031. The reversal of 18142021 is 12024181.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17313921 + 828100 = 4161^2 + 910^2 .

It is a cyclic number.

It is not a de Polignac number, because 18142021 - 2⁵ = 18141989 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 18142021.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (18142031) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9071010 + 9071011.

It is an arithmetic number, because the mean of its divisors is an integer number (9071011).

Almost surely, 2^18142021 is an apocalyptic number.

It is an amenable number.

18142021 is a deficient number, since it is larger than the sum of its proper divisors (1).

18142021 is an equidigital number, since it uses as much as digits as its factorization.

18142021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 128, while the sum is 19.

The square root of 18142021 is about 4259.3451374595. The cubic root of 18142021 is about 262.7615943991.

The spelling of 18142021 in words is "eighteen million, one hundred forty-two thousand, twenty-one".