19991444 has 12 divisors (see below), whose sum is σ = 38165568. Its totient is φ = 9087000.

The previous prime is 19991429. The next prime is 19991467. The reversal of 19991444 is 44419991.

It is a happy number.

It is a congruent number.

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, 227132 + ... + 227219.

It is an arithmetic number, because the mean of its divisors is an integer number (3180464).

Almost surely, 2^19991444 is an apocalyptic number.

It is an amenable number.

19991444 is a deficient number, since it is larger than the sum of its proper divisors (18174124).

19991444 is a wasteful number, since it uses less digits than its factorization.

19991444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 454366 (or 454364 counting only the distinct ones).

The product of its digits is 46656, while the sum is 41.

The square root of 19991444 is about 4471.1792627896. The cubic root of 19991444 is about 271.4030485433.

It can be divided in two parts, 1999 and 1444, that added together give a palindrome (3443).

The spelling of 19991444 in words is "nineteen million, nine hundred ninety-one thousand, four hundred forty-four".