90745409 has 4 divisors (see below), whose sum is σ = 90765780. Its totient is φ = 90725040.

The previous prime is 90745397. The next prime is 90745411. The reversal of 90745409 is 90454709.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 60528400 + 30217009 = 7780^2 + 5497^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-90745409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90745469) 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 3 ways as a sum of consecutive naturals, for example, 314 + ... + 13475.

It is an arithmetic number, because the mean of its divisors is an integer number (22691445).

Almost surely, 2^90745409 is an apocalyptic number.

It is an amenable number.

90745409 is a deficient number, since it is larger than the sum of its proper divisors (20371).

90745409 is a wasteful number, since it uses less digits than its factorization.

90745409 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20370.

The product of its (nonzero) digits is 45360, while the sum is 38.

The square root of 90745409 is about 9526.0384735734. The cubic root of 90745409 is about 449.3742892199.

The spelling of 90745409 in words is "ninety million, seven hundred forty-five thousand, four hundred nine".