90106993 has 2 divisors, whose sum is σ = 90106994. Its totient is φ = 90106992.

The previous prime is 90106967. The next prime is 90106997. The reversal of 90106993 is 39960109.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 89245809 + 861184 = 9447^2 + 928^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90106993 is a prime.

It is not a weakly prime, because it can be changed into another prime (90106997) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45053496 + 45053497.

It is an arithmetic number, because the mean of its divisors is an integer number (45053497).

Almost surely, 2^90106993 is an apocalyptic number.

It is an amenable number.

90106993 is a deficient number, since it is larger than the sum of its proper divisors (1).

90106993 is an equidigital number, since it uses as much as digits as its factorization.

90106993 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 13122, while the sum is 37.

The square root of 90106993 is about 9492.4703317946. The cubic root of 90106993 is about 448.3179891224.

The spelling of 90106993 in words is "ninety million, one hundred six thousand, nine hundred ninety-three".