28236831 has 16 divisors (see below), whose sum is σ = 45292800. Its totient is φ = 15285888.

The previous prime is 28236827. The next prime is 28236833. The reversal of 28236831 is 13863282.

It is not a de Polignac number, because 28236831 - 2² = 28236827 is a prime.

It is a super-2 number, since 2×28236831² = 1594637249845122, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 28236792 and 28236801.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (28236833) 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, 34986 + ... + 35783.

It is an arithmetic number, because the mean of its divisors is an integer number (2830800).

Almost surely, 2^28236831 is an apocalyptic number.

28236831 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

28236831 is a deficient number, since it is larger than the sum of its proper divisors (17055969).

28236831 is a wasteful number, since it uses less digits than its factorization.

28236831 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 70798.

The product of its digits is 13824, while the sum is 33.

The square root of 28236831 is about 5313.8339266484. The cubic root of 28236831 is about 304.5126356042.

The spelling of 28236831 in words is "twenty-eight million, two hundred thirty-six thousand, eight hundred thirty-one".