9121999 has 2 divisors, whose sum is σ = 9122000. Its totient is φ = 9121998.

The previous prime is 9121993. The next prime is 9122021. The reversal of 9121999 is 9991219.

9121999 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 is a cyclic number.

It is not a de Polignac number, because 9121999 - 2¹¹ = 9119951 is a prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (9121993) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4560999 + 4561000.

It is an arithmetic number, because the mean of its divisors is an integer number (4561000).

Almost surely, 2^9121999 is an apocalyptic number.

9121999 is a deficient number, since it is larger than the sum of its proper divisors (1).

9121999 is an equidigital number, since it uses as much as digits as its factorization.

9121999 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13122, while the sum is 40.

The square root of 9121999 is about 3020.2647234969. The cubic root of 9121999 is about 208.9440491850.

The spelling of 9121999 in words is "nine million, one hundred twenty-one thousand, nine hundred ninety-nine".