28266231 has 16 divisors (see below), whose sum is σ = 43593984. Its totient is φ = 15956544.

The previous prime is 28266221. The next prime is 28266239. The reversal of 28266231 is 13266282.

It is not a de Polignac number, because 28266231 - 2⁹ = 28265719 is a prime.

It is a super-2 number, since 2×28266231² = 1597959629890722, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28266239) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6366 + ... + 9851.

It is an arithmetic number, because the mean of its divisors is an integer number (2724624).

Almost surely, 2^28266231 is an apocalyptic number.

28266231 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28266231 is a deficient number, since it is larger than the sum of its proper divisors (15327753).

28266231 is a wasteful number, since it uses less digits than its factorization.

28266231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16310.

The product of its digits is 6912, while the sum is 30.

The square root of 28266231 is about 5316.5995711545. The cubic root of 28266231 is about 304.6182844538.

The spelling of 28266231 in words is "twenty-eight million, two hundred sixty-six thousand, two hundred thirty-one".