19521760997 has 2 divisors, whose sum is σ = 19521760998. Its totient is φ = 19521760996.

The previous prime is 19521760949. The next prime is 19521761023. The reversal of 19521760997 is 79906712591.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18846072961 + 675688036 = 137281^2 + 25994^2 .

It is a cyclic number.

It is not a de Polignac number, because 19521760997 - 2¹² = 19521756901 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (19521760697) 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, 9760880498 + 9760880499.

It is an arithmetic number, because the mean of its divisors is an integer number (9760880499).

Almost surely, 2^19521760997 is an apocalyptic number.

It is an amenable number.

19521760997 is a deficient number, since it is larger than the sum of its proper divisors (1).

19521760997 is an equidigital number, since it uses as much as digits as its factorization.

19521760997 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2143260, while the sum is 56.

The spelling of 19521760997 in words is "nineteen billion, five hundred twenty-one million, seven hundred sixty thousand, nine hundred ninety-seven".