33728730 has 64 divisors (see below), whose sum is σ = 94065408. Its totient is φ = 7580160.

The previous prime is 33728729. The next prime is 33728749. The reversal of 33728730 is 3782733.

It is a happy number.

It is a super-2 number, since 2×33728730² = 2275254454825800, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 33728691 and 33728700.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 11494 + ... + 14126.

It is an arithmetic number, because the mean of its divisors is an integer number (1469772).

Almost surely, 2^33728730 is an apocalyptic number.

33728730 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 33728730, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (47032704).

33728730 is an abundant number, since it is smaller than the sum of its proper divisors (60336678).

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

33728730 is a wasteful number, since it uses less digits than its factorization.

33728730 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2711.

The product of its (nonzero) digits is 21168, while the sum is 33.

The square root of 33728730 is about 5807.6441006659. The cubic root of 33728730 is about 323.0973006072.

The spelling of 33728730 in words is "thirty-three million, seven hundred twenty-eight thousand, seven hundred thirty".