19430776021 has 4 divisors (see below), whose sum is σ = 19623160044. Its totient is φ = 19238392000.

The previous prime is 19430776007. The next prime is 19430776067. The reversal of 19430776021 is 12067703491.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 13016528100 + 6414247921 = 114090^2 + 80089^2 .

It is a cyclic number.

It is not a de Polignac number, because 19430776021 - 2¹⁵ = 19430743253 is a prime.

It is a Smith number, since the sum of its digits (40) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19430776091) 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, 96191860 + ... + 96192061.

It is an arithmetic number, because the mean of its divisors is an integer number (4905790011).

Almost surely, 2^19430776021 is an apocalyptic number.

It is an amenable number.

19430776021 is a deficient number, since it is larger than the sum of its proper divisors (192384023).

19430776021 is a wasteful number, since it uses less digits than its factorization.

19430776021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 192384022.

The product of its (nonzero) digits is 63504, while the sum is 40.

The spelling of 19430776021 in words is "nineteen billion, four hundred thirty million, seven hundred seventy-six thousand, twenty-one".