19897844 has 12 divisors (see below), whose sum is σ = 34978944. Its totient is φ = 9903864.

The previous prime is 19897789. The next prime is 19897847. The reversal of 19897844 is 44879891.

It is a junction number, because it is equal to n+sod(n) for n = 19897792 and 19897801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19897847) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10262 + ... + 12045.

It is an arithmetic number, because the mean of its divisors is an integer number (2914912).

Almost surely, 2^19897844 is an apocalyptic number.

It is an amenable number.

19897844 is a deficient number, since it is larger than the sum of its proper divisors (15081100).

19897844 is a wasteful number, since it uses less digits than its factorization.

19897844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22534 (or 22532 counting only the distinct ones).

The product of its digits is 580608, while the sum is 50.

The square root of 19897844 is about 4460.6999450759. The cubic root of 19897844 is about 270.9788158075.

The spelling of 19897844 in words is "nineteen million, eight hundred ninety-seven thousand, eight hundred forty-four".