33728231 has 2 divisors, whose sum is σ = 33728232. Its totient is φ = 33728230.

The previous prime is 33728213. The next prime is 33728237. The reversal of 33728231 is 13282733.

Together with previous prime (33728213) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is an emirp because it is prime and its reverse (13282733) is a distict prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-33728231 is a prime.

It is a super-2 number, since 2×33728231² = 2275187132778722, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 33728194 and 33728203.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (33728237) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 16864115 + 16864116.

It is an arithmetic number, because the mean of its divisors is an integer number (16864116).

Almost surely, 2^33728231 is an apocalyptic number.

33728231 is a deficient number, since it is larger than the sum of its proper divisors (1).

33728231 is an equidigital number, since it uses as much as digits as its factorization.

33728231 is an evil number, because the sum of its binary digits is even.

The product of its digits is 6048, while the sum is 29.

The square root of 33728231 is about 5807.6011398856. The cubic root of 33728231 is about 323.0957072441.

The spelling of 33728231 in words is "thirty-three million, seven hundred twenty-eight thousand, two hundred thirty-one".