19959973 has 4 divisors (see below), whose sum is σ = 21774528. Its totient is φ = 18145420.

The previous prime is 19959949. The next prime is 19959977. The reversal of 19959973 is 37995991.

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.

It is a cyclic number.

It is not a de Polignac number, because 19959973 - 2⁹ = 19959461 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 19959973.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19959977) 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, 907261 + ... + 907282.

It is an arithmetic number, because the mean of its divisors is an integer number (5443632).

Almost surely, 2^19959973 is an apocalyptic number.

It is an amenable number.

19959973 is a deficient number, since it is larger than the sum of its proper divisors (1814555).

19959973 is a wasteful number, since it uses less digits than its factorization.

19959973 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1814554.

The product of its digits is 688905, while the sum is 52.

The square root of 19959973 is about 4467.6585590217. The cubic root of 19959973 is about 271.2605573981.

The spelling of 19959973 in words is "nineteen million, nine hundred fifty-nine thousand, nine hundred seventy-three".