19973789 has 4 divisors (see below), whose sum is σ = 21789600. Its totient is φ = 18157980.

The previous prime is 19973773. The next prime is 19973803. The reversal of 19973789 is 98737991.

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 19973789 - 2⁴ = 19973773 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 19973789.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19973189) 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, 907889 + ... + 907910.

It is an arithmetic number, because the mean of its divisors is an integer number (5447400).

Almost surely, 2^19973789 is an apocalyptic number.

It is an amenable number.

19973789 is a deficient number, since it is larger than the sum of its proper divisors (1815811).

19973789 is a wasteful number, since it uses less digits than its factorization.

19973789 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1815810.

The product of its digits is 857304, while the sum is 53.

The square root of 19973789 is about 4469.2045153472. The cubic root of 19973789 is about 271.3231304868.

The spelling of 19973789 in words is "nineteen million, nine hundred seventy-three thousand, seven hundred eighty-nine".