28673681 has 2 divisors, whose sum is σ = 28673682. Its totient is φ = 28673680.

The previous prime is 28673677. The next prime is 28673707. The reversal of 28673681 is 18637682.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24910081 + 3763600 = 4991^2 + 1940^2 .

It is a cyclic number.

It is not a de Polignac number, because 28673681 - 2² = 28673677 is a prime.

It is a super-2 number, since 2×28673681² = 1644359964179522, which contains 22 as substring.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (28673621) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 14336840 + 14336841.

It is an arithmetic number, because the mean of its divisors is an integer number (14336841).

Almost surely, 2^28673681 is an apocalyptic number.

It is an amenable number.

28673681 is a deficient number, since it is larger than the sum of its proper divisors (1).

28673681 is an equidigital number, since it uses as much as digits as its factorization.

28673681 is an evil number, because the sum of its binary digits is even.

The product of its digits is 96768, while the sum is 41.

The square root of 28673681 is about 5354.7811346497. The cubic root of 28673681 is about 306.0749705949.

The spelling of 28673681 in words is "twenty-eight million, six hundred seventy-three thousand, six hundred eighty-one".