19720444 has 12 divisors (see below), whose sum is σ = 34577704. Its totient is φ = 9841104.

The previous prime is 19720403. The next prime is 19720447. The reversal of 19720444 is 44402791.

It is a hoax number, since the sum of its digits (31) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19720447) 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, 2319 + ... + 6694.

Almost surely, 2^19720444 is an apocalyptic number.

It is an amenable number.

19720444 is a deficient number, since it is larger than the sum of its proper divisors (14857260).

19720444 is a wasteful number, since it uses less digits than its factorization.

19720444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9564 (or 9562 counting only the distinct ones).

The product of its (nonzero) digits is 8064, while the sum is 31.

The square root of 19720444 is about 4440.7706538393. The cubic root of 19720444 is about 270.1711032518.

It can be divided in two parts, 19720 and 444, that added together give a square (20164 = 142²).

The spelling of 19720444 in words is "nineteen million, seven hundred twenty thousand, four hundred forty-four".