19811444 has 6 divisors (see below), whose sum is σ = 34670034. Its totient is φ = 9905720.

The previous prime is 19811417. The next prime is 19811479. The reversal of 19811444 is 44411891.

It can be written as a sum of positive squares in only one way, i.e., 19695844 + 115600 = 4438^2 + 340^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 19811444.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 2476427 + ... + 2476434.

It is an arithmetic number, because the mean of its divisors is an integer number (5778339).

Almost surely, 2^19811444 is an apocalyptic number.

It is an amenable number.

19811444 is a deficient number, since it is larger than the sum of its proper divisors (14858590).

19811444 is a wasteful number, since it uses less digits than its factorization.

19811444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4952865 (or 4952863 counting only the distinct ones).

The product of its digits is 4608, while the sum is 32.

The square root of 19811444 is about 4451.0048303726. The cubic root of 19811444 is about 270.5860339085.

The spelling of 19811444 in words is "nineteen million, eight hundred eleven thousand, four hundred forty-four".