33728947 has 4 divisors (see below), whose sum is σ = 38547376. Its totient is φ = 28910520.

The previous prime is 33728923. The next prime is 33728957. The reversal of 33728947 is 74982733.

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

It is a cyclic number.

It is not a de Polignac number, because 33728947 - 2¹¹ = 33726899 is a prime.

It is a super-2 number, since 2×33728947² = 2275283731457618, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (33728957) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2409204 + ... + 2409217.

It is an arithmetic number, because the mean of its divisors is an integer number (9636844).

Almost surely, 2^33728947 is an apocalyptic number.

33728947 is a deficient number, since it is larger than the sum of its proper divisors (4818429).

33728947 is an equidigital number, since it uses as much as digits as its factorization.

33728947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4818428.

The product of its digits is 254016, while the sum is 43.

The square root of 33728947 is about 5807.6627829102. The cubic root of 33728947 is about 323.0979935078.

The spelling of 33728947 in words is "thirty-three million, seven hundred twenty-eight thousand, nine hundred forty-seven".