28336661 has 4 divisors (see below), whose sum is σ = 28617324. Its totient is φ = 28056000.

The previous prime is 28336631. The next prime is 28336681. The reversal of 28336661 is 16663382.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 16663382 = 2 ⋅8331691.

It can be written as a sum of positive squares in 2 ways, for example, as 11771761 + 16564900 = 3431^2 + 4070^2 .

It is a cyclic number.

It is not a de Polignac number, because 28336661 - 2²² = 24142357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28336631) 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, 140180 + ... + 140381.

It is an arithmetic number, because the mean of its divisors is an integer number (7154331).

Almost surely, 2^28336661 is an apocalyptic number.

It is an amenable number.

28336661 is a deficient number, since it is larger than the sum of its proper divisors (280663).

28336661 is a wasteful number, since it uses less digits than its factorization.

28336661 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 280662.

The product of its digits is 31104, while the sum is 35.

The square root of 28336661 is about 5323.2190449013. The cubic root of 28336661 is about 304.8710769284.

The spelling of 28336661 in words is "twenty-eight million, three hundred thirty-six thousand, six hundred sixty-one".