33689728 has 16 divisors (see below), whose sum is σ = 67116510. Its totient is φ = 16844800.

The previous prime is 33689701. The next prime is 33689729. The reversal of 33689728 is 82798633.

It can be written as a sum of positive squares in only one way, i.e., 33269824 + 419904 = 5768^2 + 648^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is a super-2 number, since 2×33689728² = 2269995545427968, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (33689729) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 131473 + ... + 131728.

Almost surely, 2^33689728 is an apocalyptic number.

It is an amenable number.

33689728 is a deficient number, since it is larger than the sum of its proper divisors (33426782).

33689728 is an equidigital number, since it uses as much as digits as its factorization.

33689728 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 263215 (or 263203 counting only the distinct ones).

The product of its digits is 435456, while the sum is 46.

The square root of 33689728 is about 5804.2853134559. The cubic root of 33689728 is about 322.9727154120.

The spelling of 33689728 in words is "thirty-three million, six hundred eighty-nine thousand, seven hundred twenty-eight".