90728849 has 4 divisors (see below), whose sum is σ = 93857460. Its totient is φ = 87600240.

The previous prime is 90728821. The next prime is 90728851. The reversal of 90728849 is 94882709.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 25684624 + 65044225 = 5068^2 + 8065^2 .

It is a cyclic number.

It is not a de Polignac number, because 90728849 - 2⁸ = 90728593 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (90728809) 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, 1564262 + ... + 1564319.

It is an arithmetic number, because the mean of its divisors is an integer number (23464365).

Almost surely, 2^90728849 is an apocalyptic number.

It is an amenable number.

90728849 is a deficient number, since it is larger than the sum of its proper divisors (3128611).

90728849 is a wasteful number, since it uses less digits than its factorization.

90728849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3128610.

The product of its (nonzero) digits is 290304, while the sum is 47.

The square root of 90728849 is about 9525.1692373417. The cubic root of 90728849 is about 449.3469523330.

The spelling of 90728849 in words is "ninety million, seven hundred twenty-eight thousand, eight hundred forty-nine".