28000681 has 4 divisors (see below), whose sum is σ = 28355200. Its totient is φ = 27646164.

The previous prime is 28000613. The next prime is 28000691. The reversal of 28000681 is 18600082.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-28000681 is a prime.

It is a super-2 number, since 2×28000681² = 1568076272927522, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (28000691) 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, 177141 + ... + 177298.

It is an arithmetic number, because the mean of its divisors is an integer number (7088800).

Almost surely, 2^28000681 is an apocalyptic number.

It is an amenable number.

28000681 is a deficient number, since it is larger than the sum of its proper divisors (354519).

28000681 is an equidigital number, since it uses as much as digits as its factorization.

28000681 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 354518.

The product of its (nonzero) digits is 768, while the sum is 25.

The square root of 28000681 is about 5291.5669701895. The cubic root of 28000681 is about 303.6613589737.

The spelling of 28000681 in words is "twenty-eight million, six hundred eighty-one", and thus it is an aban number.