99247021 has 2 divisors, whose sum is σ = 99247022. Its totient is φ = 99247020.

The previous prime is 99246977. The next prime is 99247039. The reversal of 99247021 is 12074299.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 95824521 + 3422500 = 9789^2 + 1850^2 .

It is an emirp because it is prime and its reverse (12074299) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99247021 - 2⁹ = 99246509 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (99247081) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49623510 + 49623511.

It is an arithmetic number, because the mean of its divisors is an integer number (49623511).

Almost surely, 2^99247021 is an apocalyptic number.

It is an amenable number.

99247021 is a deficient number, since it is larger than the sum of its proper divisors (1).

99247021 is an equidigital number, since it uses as much as digits as its factorization.

99247021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 9072, while the sum is 34.

The square root of 99247021 is about 9962.2799097395. The cubic root of 99247021 is about 462.9909406771.

The spelling of 99247021 in words is "ninety-nine million, two hundred forty-seven thousand, twenty-one".