90521009 has 2 divisors, whose sum is σ = 90521010. Its totient is φ = 90521008.

The previous prime is 90521003. The next prime is 90521029. The reversal of 90521009 is 90012509.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 73273600 + 17247409 = 8560^2 + 4153^2 .

It is a cyclic number.

It is not a de Polignac number, because 90521009 - 2⁸ = 90520753 is a prime.

It is not a weakly prime, because it can be changed into another prime (90521003) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45260504 + 45260505.

It is an arithmetic number, because the mean of its divisors is an integer number (45260505).

Almost surely, 2^90521009 is an apocalyptic number.

It is an amenable number.

90521009 is a deficient number, since it is larger than the sum of its proper divisors (1).

90521009 is an equidigital number, since it uses as much as digits as its factorization.

90521009 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 810, while the sum is 26.

The square root of 90521009 is about 9514.2529396690. The cubic root of 90521009 is about 449.0035713824.

The spelling of 90521009 in words is "ninety million, five hundred twenty-one thousand, nine".