33280640 has 64 divisors (see below), whose sum is σ = 80325000. Its totient is φ = 13185024.

The previous prime is 33280607. The next prime is 33280657. The reversal of 33280640 is 4608233.

It can be written as a sum of positive squares in 4 ways, for example, as 23892544 + 9388096 = 4888^2 + 3064^2 .

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×33280640² = 2215201997619200, which contains 22 as substring.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 95186 + ... + 95534.

Almost surely, 2^33280640 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 33280640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (40162500).

33280640 is an abundant number, since it is smaller than the sum of its proper divisors (47044360).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

33280640 is a wasteful number, since it uses less digits than its factorization.

33280640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 517 (or 505 counting only the distinct ones).

The product of its (nonzero) digits is 3456, while the sum is 26.

The square root of 33280640 is about 5768.9375104953. The cubic root of 33280640 is about 321.6601225846.

Adding to 33280640 its reverse (4608233), we get a palindrome (37888873).

The spelling of 33280640 in words is "thirty-three million, two hundred eighty thousand, six hundred forty".