33505440 has 144 divisors (see below), whose sum is σ = 110623968. Its totient is φ = 8522752.

The previous prime is 33505403. The next prime is 33505441. The reversal of 33505440 is 4450533.

It is a happy number.

It is a super-2 number, since 2×33505440² = 2245229019187200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 33505440.

It is not an unprimeable number, because it can be changed into a prime (33505441) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 403639 + ... + 403721.

It is an arithmetic number, because the mean of its divisors is an integer number (768222).

Almost surely, 2^33505440 is an apocalyptic number.

33505440 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 33505440, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (55311984).

33505440 is an abundant number, since it is smaller than the sum of its proper divisors (77118528).

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

33505440 is a wasteful number, since it uses less digits than its factorization.

33505440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 159 (or 122 counting only the distinct ones).

The product of its (nonzero) digits is 3600, while the sum is 24.

The square root of 33505440 is about 5788.3883767418. The cubic root of 33505440 is about 322.3827348434.

Adding to 33505440 its reverse (4450533), we get a palindrome (37955973).

The spelling of 33505440 in words is "thirty-three million, five hundred five thousand, four hundred forty".