90905689 has 4 divisors (see below), whose sum is σ = 103892224. Its totient is φ = 77919156.

The previous prime is 90905663. The next prime is 90905693. The reversal of 90905689 is 98650909.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 90905689 - 2¹³ = 90897497 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90906689) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6493257 + ... + 6493270.

It is an arithmetic number, because the mean of its divisors is an integer number (25973056).

Almost surely, 2^90905689 is an apocalyptic number.

It is an amenable number.

90905689 is a deficient number, since it is larger than the sum of its proper divisors (12986535).

90905689 is a wasteful number, since it uses less digits than its factorization.

90905689 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12986534.

The product of its (nonzero) digits is 174960, while the sum is 46.

The square root of 90905689 is about 9534.4474931692. The cubic root of 90905689 is about 449.6387042394.

The spelling of 90905689 in words is "ninety million, nine hundred five thousand, six hundred eighty-nine".