33725821 has 4 divisors (see below), whose sum is σ = 34548444. Its totient is φ = 32903200.

The previous prime is 33725789. The next prime is 33725827. The reversal of 33725821 is 12852733.

33725821 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 5784025 + 27941796 = 2405^2 + 5286^2 .

It is a cyclic number.

It is not a de Polignac number, because 33725821 - 2⁵ = 33725789 is a prime.

It is a super-2 number, since 2×33725821² = 2274862004248082, which contains 22 as substring.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33725827) 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 3 ways as a sum of consecutive naturals, for example, 411250 + ... + 411331.

It is an arithmetic number, because the mean of its divisors is an integer number (8637111).

Almost surely, 2^33725821 is an apocalyptic number.

It is an amenable number.

33725821 is a deficient number, since it is larger than the sum of its proper divisors (822623).

33725821 is an equidigital number, since it uses as much as digits as its factorization.

33725821 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 822622.

The product of its digits is 10080, while the sum is 31.

The square root of 33725821 is about 5807.3936494782. The cubic root of 33725821 is about 323.0880116216.

The spelling of 33725821 in words is "thirty-three million, seven hundred twenty-five thousand, eight hundred twenty-one".