90920993 has 2 divisors, whose sum is σ = 90920994. Its totient is φ = 90920992.

The previous prime is 90920957. The next prime is 90921011. The reversal of 90920993 is 39902909.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 63808144 + 27112849 = 7988^2 + 5207^2 .

It is a cyclic number.

It is not a de Polignac number, because 90920993 - 2²⁴ = 74143777 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 90920993.

It is not a weakly prime, because it can be changed into another prime (90920953) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45460496 + 45460497.

It is an arithmetic number, because the mean of its divisors is an integer number (45460497).

Almost surely, 2^90920993 is an apocalyptic number.

It is an amenable number.

90920993 is a deficient number, since it is larger than the sum of its proper divisors (1).

90920993 is an equidigital number, since it uses as much as digits as its factorization.

90920993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 39366, while the sum is 41.

The square root of 90920993 is about 9535.2500229412. The cubic root of 90920993 is about 449.6639350938.

The spelling of 90920993 in words is "ninety million, nine hundred twenty thousand, nine hundred ninety-three".