28336681 has 2 divisors, whose sum is σ = 28336682. Its totient is φ = 28336680.

The previous prime is 28336631. The next prime is 28336691. The reversal of 28336681 is 18663382.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 27920656 + 416025 = 5284^2 + 645^2 .

It is a cyclic number.

It is not a de Polignac number, because 28336681 - 2⁹ = 28336169 is a prime.

It is a super-2 number, since 2×28336681² = 1605934980191522, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 28336681.

It is not a weakly prime, because it can be changed into another prime (28336631) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14168340 + 14168341.

It is an arithmetic number, because the mean of its divisors is an integer number (14168341).

Almost surely, 2^28336681 is an apocalyptic number.

It is an amenable number.

28336681 is a deficient number, since it is larger than the sum of its proper divisors (1).

28336681 is an equidigital number, since it uses as much as digits as its factorization.

28336681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 41472, while the sum is 37.

The square root of 28336681 is about 5323.2209234635. The cubic root of 28336681 is about 304.8711486543.

The spelling of 28336681 in words is "twenty-eight million, three hundred thirty-six thousand, six hundred eighty-one".