18986121 has 24 divisors (see below), whose sum is σ = 34192704. Its totient is φ = 9862560.

The previous prime is 18986117. The next prime is 18986129. The reversal of 18986121 is 12168981.

It is not a de Polignac number, because 18986121 - 2² = 18986117 is a prime.

It is not an unprimeable number, because it can be changed into a prime (18986129) 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, 13006 + ... + 14391.

It is an arithmetic number, because the mean of its divisors is an integer number (1424696).

Almost surely, 2^18986121 is an apocalyptic number.

18986121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

18986121 is a deficient number, since it is larger than the sum of its proper divisors (15206583).

18986121 is a wasteful number, since it uses less digits than its factorization.

18986121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27421 (or 27418 counting only the distinct ones).

The product of its digits is 6912, while the sum is 36.

The square root of 18986121 is about 4357.3066222152. The cubic root of 18986121 is about 266.7751758059.

The spelling of 18986121 in words is "eighteen million, nine hundred eighty-six thousand, one hundred twenty-one".