33405221 has 6 divisors (see below), whose sum is σ = 35486130. Its totient is φ = 31439936.

The previous prime is 33405217. The next prime is 33405241. The reversal of 33405221 is 12250433.

It is a happy number.

It can be written as a sum of positive squares in 3 ways, for example, as 20802721 + 12602500 = 4561^2 + 3550^2 .

It is not a de Polignac number, because 33405221 - 2² = 33405217 is a prime.

It is a super-2 number, since 2×33405221² = 2231817580117682, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 33405193 and 33405202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (33405241) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 57506 + ... + 58083.

It is an arithmetic number, because the mean of its divisors is an integer number (5914355).

Almost surely, 2^33405221 is an apocalyptic number.

It is an amenable number.

33405221 is a deficient number, since it is larger than the sum of its proper divisors (2080909).

33405221 is a wasteful number, since it uses less digits than its factorization.

33405221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 115623 (or 115606 counting only the distinct ones).

The product of its (nonzero) digits is 720, while the sum is 20.

The square root of 33405221 is about 5779.7249934577. The cubic root of 33405221 is about 322.0609846813.

Adding to 33405221 its reverse (12250433), we get a palindrome (45655654).

The spelling of 33405221 in words is "thirty-three million, four hundred five thousand, two hundred twenty-one".