18913444 has 12 divisors (see below), whose sum is σ = 36107568. Its totient is φ = 8597000.

The previous prime is 18913403. The next prime is 18913457. The reversal of 18913444 is 44431981.

It is a super-2 number, since 2×18913444² = 715436727882272, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 214882 + ... + 214969.

It is an arithmetic number, because the mean of its divisors is an integer number (3008964).

Almost surely, 2^18913444 is an apocalyptic number.

It is an amenable number.

18913444 is a deficient number, since it is larger than the sum of its proper divisors (17194124).

18913444 is a wasteful number, since it uses less digits than its factorization.

18913444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 429866 (or 429864 counting only the distinct ones).

The product of its digits is 13824, while the sum is 34.

The square root of 18913444 is about 4348.9589558882. The cubic root of 18913444 is about 266.4343441850.

It can be divided in two parts, 1891 and 3444, that added together give a palindrome (5335).

The spelling of 18913444 in words is "eighteen million, nine hundred thirteen thousand, four hundred forty-four".