28103331 has 12 divisors (see below), whose sum is σ = 37809368. Its totient is φ = 18567744.

The previous prime is 28103323. The next prime is 28103347. The reversal of 28103331 is 13330182.

It is a happy number.

It is not a de Polignac number, because 28103331 - 2³ = 28103323 is a prime.

It is a super-2 number, since 2×28103331² = 1579594426591122, which contains 22 as substring.

It is a hoax number, since the sum of its digits (21) coincides with the sum of the digits of its distinct prime factors.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 28103298 and 28103307.

It is not an unprimeable number, because it can be changed into a prime (28103531) 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 11 ways as a sum of consecutive naturals, for example, 89631 + ... + 89943.

Almost surely, 2^28103331 is an apocalyptic number.

28103331 is a deficient number, since it is larger than the sum of its proper divisors (9706037).

28103331 is an equidigital number, since it uses as much as digits as its factorization.

28103331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 662 (or 489 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 21.

The square root of 28103331 is about 5301.2574923314. The cubic root of 28103331 is about 304.0319788324.

The spelling of 28103331 in words is "twenty-eight million, one hundred three thousand, three hundred thirty-one".