90881689 has 2 divisors, whose sum is σ = 90881690. Its totient is φ = 90881688.

The previous prime is 90881683. The next prime is 90881723. The reversal of 90881689 is 98618809.

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., 90878089 + 3600 = 9533^2 + 60^2 .

It is a cyclic number.

It is not a de Polignac number, because 90881689 - 2¹⁵ = 90848921 is a prime.

It is not a weakly prime, because it can be changed into another prime (90881683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45440844 + 45440845.

It is an arithmetic number, because the mean of its divisors is an integer number (45440845).

Almost surely, 2^90881689 is an apocalyptic number.

It is an amenable number.

90881689 is a deficient number, since it is larger than the sum of its proper divisors (1).

90881689 is an equidigital number, since it uses as much as digits as its factorization.

90881689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 248832, while the sum is 49.

The square root of 90881689 is about 9533.1888159209. The cubic root of 90881689 is about 449.5991310699.

The spelling of 90881689 in words is "ninety million, eight hundred eighty-one thousand, six hundred eighty-nine".