8721999497 has 2 divisors, whose sum is σ = 8721999498. Its totient is φ = 8721999496.

The previous prime is 8721999493. The next prime is 8721999511. The reversal of 8721999497 is 7949991278.

8721999497 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7469972041 + 1252027456 = 86429^2 + 35384^2 .

It is a cyclic number.

It is not a de Polignac number, because 8721999497 - 2² = 8721999493 is a prime.

It is not a weakly prime, because it can be changed into another prime (8721999493) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4360999748 + 4360999749.

It is an arithmetic number, because the mean of its divisors is an integer number (4360999749).

Almost surely, 2^8721999497 is an apocalyptic number.

It is an amenable number.

8721999497 is a deficient number, since it is larger than the sum of its proper divisors (1).

8721999497 is an equidigital number, since it uses as much as digits as its factorization.

8721999497 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 20575296, while the sum is 65.

The square root of 8721999497 is about 93391.6457559240. The cubic root of 8721999497 is about 2058.4422427770.

The spelling of 8721999497 in words is "eight billion, seven hundred twenty-one million, nine hundred ninety-nine thousand, four hundred ninety-seven".