18882021 has 4 divisors (see below), whose sum is σ = 25176032. Its totient is φ = 12588012.

The previous prime is 18882013. The next prime is 18882023. The reversal of 18882021 is 12028881.

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.

It is not a de Polignac number, because 18882021 - 2³ = 18882013 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 18882021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18882023) 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, 3147001 + ... + 3147006.

It is an arithmetic number, because the mean of its divisors is an integer number (6294008).

Almost surely, 2^18882021 is an apocalyptic number.

It is an amenable number.

18882021 is a deficient number, since it is larger than the sum of its proper divisors (6294011).

18882021 is an equidigital number, since it uses as much as digits as its factorization.

18882021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6294010.

The product of its (nonzero) digits is 2048, while the sum is 30.

The square root of 18882021 is about 4345.3447504197. The cubic root of 18882021 is about 266.2867100962.

The spelling of 18882021 in words is "eighteen million, eight hundred eighty-two thousand, twenty-one".