19743973 has 4 divisors (see below), whose sum is σ = 19754080. Its totient is φ = 19733868.

The previous prime is 19743949. The next prime is 19743989. The reversal of 19743973 is 37934791.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 37934791 = 5521 ⋅6871.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-19743973 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19743173) 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, 1083 + ... + 6376.

It is an arithmetic number, because the mean of its divisors is an integer number (4938520).

Almost surely, 2^19743973 is an apocalyptic number.

It is an amenable number.

19743973 is a deficient number, since it is larger than the sum of its proper divisors (10107).

19743973 is an equidigital number, since it uses as much as digits as its factorization.

19743973 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10106.

The product of its digits is 142884, while the sum is 43.

The square root of 19743973 is about 4443.4190664397. The cubic root of 19743973 is about 270.2785100523.

The spelling of 19743973 in words is "nineteen million, seven hundred forty-three thousand, nine hundred seventy-three".