18923986 has 16 divisors (see below), whose sum is σ = 30253824. Its totient is φ = 8857024.

The previous prime is 18923953. The next prime is 18923987. The reversal of 18923986 is 68932981.

It is a super-2 number, since 2×18923986² = 716234492256392, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (46).

It is not an unprimeable number, because it can be changed into a prime (18923987) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2215 + ... + 6538.

It is an arithmetic number, because the mean of its divisors is an integer number (1890864).

Almost surely, 2^18923986 is an apocalyptic number.

18923986 is a deficient number, since it is larger than the sum of its proper divisors (11329838).

18923986 is a wasteful number, since it uses less digits than its factorization.

18923986 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8825.

The product of its digits is 186624, while the sum is 46.

The square root of 18923986 is about 4350.1708012445. The cubic root of 18923986 is about 266.4838368311.

It can be divided in two parts, 189 and 23986, that multiplied together give a palindrome (4533354).

The spelling of 18923986 in words is "eighteen million, nine hundred twenty-three thousand, nine hundred eighty-six".