90099091 has 2 divisors, whose sum is σ = 90099092. Its totient is φ = 90099090.

The previous prime is 90099001. The next prime is 90099101. The reversal of 90099091 is 19099009.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 90099091 - 2¹¹ = 90097043 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 90099091.

It is not a weakly prime, because it can be changed into another prime (90099001) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45049545 + 45049546.

It is an arithmetic number, because the mean of its divisors is an integer number (45049546).

Almost surely, 2^90099091 is an apocalyptic number.

90099091 is a deficient number, since it is larger than the sum of its proper divisors (1).

90099091 is an equidigital number, since it uses as much as digits as its factorization.

90099091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6561, while the sum is 37.

The square root of 90099091 is about 9492.0540980338. The cubic root of 90099091 is about 448.3048835458.

The spelling of 90099091 in words is "ninety million, ninety-nine thousand, ninety-one".