99916121 has 2 divisors, whose sum is σ = 99916122. Its totient is φ = 99916120.

The previous prime is 99916073. The next prime is 99916151. The reversal of 99916121 is 12161999.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73342096 + 26574025 = 8564^2 + 5155^2 .

It is an emirp because it is prime and its reverse (12161999) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 99916121 - 2¹⁰ = 99915097 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (99916151) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49958060 + 49958061.

It is an arithmetic number, because the mean of its divisors is an integer number (49958061).

Almost surely, 2^99916121 is an apocalyptic number.

It is an amenable number.

99916121 is a deficient number, since it is larger than the sum of its proper divisors (1).

99916121 is an equidigital number, since it uses as much as digits as its factorization.

99916121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 8748, while the sum is 38.

The square root of 99916121 is about 9995.8051701701. The cubic root of 99916121 is about 464.0290697825.

The spelling of 99916121 in words is "ninety-nine million, nine hundred sixteen thousand, one hundred twenty-one".