19594174921 has 2 divisors, whose sum is σ = 19594174922. Its totient is φ = 19594174920.

The previous prime is 19594174913. The next prime is 19594174937. The reversal of 19594174921 is 12947149591.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 19309881600 + 284293321 = 138960^2 + 16861^2 .

It is a cyclic number.

It is not a de Polignac number, because 19594174921 - 2³ = 19594174913 is a prime.

It is not a weakly prime, because it can be changed into another prime (19594114921) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 9797087460 + 9797087461.

It is an arithmetic number, because the mean of its divisors is an integer number (9797087461).

Almost surely, 2^19594174921 is an apocalyptic number.

It is an amenable number.

19594174921 is a deficient number, since it is larger than the sum of its proper divisors (1).

19594174921 is an equidigital number, since it uses as much as digits as its factorization.

19594174921 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 816480, while the sum is 52.

The spelling of 19594174921 in words is "nineteen billion, five hundred ninety-four million, one hundred seventy-four thousand, nine hundred twenty-one".