90415809 has 48 divisors (see below), whose sum is σ = 155810304. Its totient is φ = 49881600.

The previous prime is 90415781. The next prime is 90415811. The reversal of 90415809 is 90851409.

It is not a de Polignac number, because 90415809 - 2⁵ = 90415777 is a prime.

It is not an unprimeable number, because it can be changed into a prime (90415859) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 51307 + ... + 53039.

It is an arithmetic number, because the mean of its divisors is an integer number (3246048).

Almost surely, 2^90415809 is an apocalyptic number.

90415809 is a gapful number since it is divisible by the number (99) formed by its first and last digit.

It is an amenable number.

90415809 is a deficient number, since it is larger than the sum of its proper divisors (65394495).

90415809 is a wasteful number, since it uses less digits than its factorization.

90415809 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1798 (or 1795 counting only the distinct ones).

The product of its (nonzero) digits is 12960, while the sum is 36.

The square root of 90415809 is about 9508.7227848960. The cubic root of 90415809 is about 448.8295657884.

Subtracting 90415809 from its reverse (90851409), we obtain a square (435600 = 660²).

The spelling of 90415809 in words is "ninety million, four hundred fifteen thousand, eight hundred nine".