18886021 has 24 divisors (see below), whose sum is σ = 24640416. Its totient is φ = 14303520.

The previous prime is 18886003. The next prime is 18886051. The reversal of 18886021 is 12068881.

It is not a de Polignac number, because 18886021 - 2⁹ = 18885509 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 (18886051) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 19470 + ... + 20416.

It is an arithmetic number, because the mean of its divisors is an integer number (1026684).

Almost surely, 2^18886021 is an apocalyptic number.

18886021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18886021 is a deficient number, since it is larger than the sum of its proper divisors (5754395).

18886021 is a wasteful number, since it uses less digits than its factorization.

18886021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1009 (or 1002 counting only the distinct ones).

The product of its (nonzero) digits is 6144, while the sum is 34.

The square root of 18886021 is about 4345.8049887219. The cubic root of 18886021 is about 266.3055123143.

It can be divided in two parts, 188860 and 21, that added together give a palindrome (188881).

The spelling of 18886021 in words is "eighteen million, eight hundred eighty-six thousand, twenty-one".