90491409 has 6 divisors (see below), whose sum is σ = 130709826. Its totient is φ = 60327600.

The previous prime is 90491399. The next prime is 90491461. The reversal of 90491409 is 90419409.

It can be written as a sum of positive squares in only one way, i.e., 79121025 + 11370384 = 8895^2 + 3372^2 .

It is not a de Polignac number, because 90491409 - 2¹¹ = 90489361 is a prime.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (90491809) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 5027292 + ... + 5027309.

It is an arithmetic number, because the mean of its divisors is an integer number (21784971).

Almost surely, 2^90491409 is an apocalyptic number.

It is an amenable number.

90491409 is a deficient number, since it is larger than the sum of its proper divisors (40218417).

90491409 is a wasteful number, since it uses less digits than its factorization.

90491409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10054607 (or 10054604 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 90491409 is about 9512.6972515686. The cubic root of 90491409 is about 448.9546252694.

The spelling of 90491409 in words is "ninety million, four hundred ninety-one thousand, four hundred nine".