99718121 has 2 divisors, whose sum is σ = 99718122. Its totient is φ = 99718120.

The previous prime is 99718097. The next prime is 99718123. The reversal of 99718121 is 12181799.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 93392896 + 6325225 = 9664^2 + 2515^2 .

It is a cyclic number.

It is not a de Polignac number, because 99718121 - 2⁶ = 99718057 is a prime.

It is a super-3 number, since 3×99718121³ (a number of 25 digits) contains 333 as substring.

Together with 99718123, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (99718123) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 49859060 + 49859061.

It is an arithmetic number, because the mean of its divisors is an integer number (49859061).

Almost surely, 2^99718121 is an apocalyptic number.

It is an amenable number.

99718121 is a deficient number, since it is larger than the sum of its proper divisors (1).

99718121 is an equidigital number, since it uses as much as digits as its factorization.

99718121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9072, while the sum is 38.

The square root of 99718121 is about 9985.8961040059. The cubic root of 99718121 is about 463.7223507998.

The spelling of 99718121 in words is "ninety-nine million, seven hundred eighteen thousand, one hundred twenty-one".