90850561 has 4 divisors (see below), whose sum is σ = 91084500. Its totient is φ = 90616624.

The previous prime is 90850549. The next prime is 90850589. The reversal of 90850561 is 16505809.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16505809 = 127 ⋅129967.

It can be written as a sum of positive squares in 2 ways, for example, as 61528336 + 29322225 = 7844^2 + 5415^2 .

It is a cyclic number.

It is not a de Polignac number, because 90850561 - 2⁹ = 90850049 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (90850541) 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, 116386 + ... + 117163.

It is an arithmetic number, because the mean of its divisors is an integer number (22771125).

Almost surely, 2^90850561 is an apocalyptic number.

It is an amenable number.

90850561 is a deficient number, since it is larger than the sum of its proper divisors (233939).

90850561 is a wasteful number, since it uses less digits than its factorization.

90850561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 233938.

The product of its (nonzero) digits is 10800, while the sum is 34.

The square root of 90850561 is about 9531.5560639384. The cubic root of 90850561 is about 449.5477942897.

The spelling of 90850561 in words is "ninety million, eight hundred fifty thousand, five hundred sixty-one".