18814021 has 4 divisors (see below), whose sum is σ = 18829152. Its totient is φ = 18798892.

The previous prime is 18814013. The next prime is 18814027. The reversal of 18814021 is 12041881.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12041881 = 1583 ⋅7607.

It is a cyclic number.

It is not a de Polignac number, because 18814021 - 2³ = 18814013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18814027) 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 in 3 ways as a sum of consecutive naturals, for example, 5515 + ... + 8248.

It is an arithmetic number, because the mean of its divisors is an integer number (4707288).

Almost surely, 2^18814021 is an apocalyptic number.

It is an amenable number.

18814021 is a deficient number, since it is larger than the sum of its proper divisors (15131).

18814021 is a wasteful number, since it uses less digits than its factorization.

18814021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15130.

The product of its (nonzero) digits is 512, while the sum is 25.

The square root of 18814021 is about 4337.5132276455. The cubic root of 18814021 is about 265.9666653160.

The spelling of 18814021 in words is "eighteen million, eight hundred fourteen thousand, twenty-one".