90808561 has 8 divisors (see below), whose sum is σ = 93595040. Its totient is φ = 88052832.

The previous prime is 90808507. The next prime is 90808567. The reversal of 90808561 is 16580809.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 90808561 - 2⁷ = 90808433 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 90808561.

It is not an unprimeable number, because it can be changed into a prime (90808567) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1620 + ... + 13573.

It is an arithmetic number, because the mean of its divisors is an integer number (11699380).

Almost surely, 2^90808561 is an apocalyptic number.

It is an amenable number.

90808561 is a deficient number, since it is larger than the sum of its proper divisors (2786479).

90808561 is a wasteful number, since it uses less digits than its factorization.

90808561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15375.

The product of its (nonzero) digits is 17280, while the sum is 37.

The square root of 90808561 is about 9529.3526013051. The cubic root of 90808561 is about 449.4785086501.

The spelling of 90808561 in words is "ninety million, eight hundred eight thousand, five hundred sixty-one".