28272681 has 24 divisors (see below), whose sum is σ = 43220736. Its totient is φ = 17772480.

The previous prime is 28272679. The next prime is 28272689. The reversal of 28272681 is 18627282.

It is a happy number.

It is not a de Polignac number, because 28272681 - 2¹ = 28272679 is a prime.

It is a super-2 number, since 2×28272681² = 1598688981855522, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (28272689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 14176 + ... + 16046.

It is an arithmetic number, because the mean of its divisors is an integer number (1800864).

Almost surely, 2^28272681 is an apocalyptic number.

It is an amenable number.

28272681 is a deficient number, since it is larger than the sum of its proper divisors (14948055).

28272681 is a wasteful number, since it uses less digits than its factorization.

28272681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1973 (or 1970 counting only the distinct ones).

The product of its digits is 21504, while the sum is 36.

The square root of 28272681 is about 5317.2061272815. The cubic root of 28272681 is about 304.6414527178.

The spelling of 28272681 in words is "twenty-eight million, two hundred seventy-two thousand, six hundred eighty-one".