33213664 has 48 divisors (see below), whose sum is σ = 71907696. Its totient is φ = 14976000.

The previous prime is 33213647. The next prime is 33213703. The reversal of 33213664 is 46631233.

It is a super-2 number, since 2×33213664² = 2206294952609792, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54964 + ... + 55564.

It is an arithmetic number, because the mean of its divisors is an integer number (1498077).

Almost surely, 2^33213664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 33213664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35953848).

33213664 is an abundant number, since it is smaller than the sum of its proper divisors (38694032).

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

33213664 is a wasteful number, since it uses less digits than its factorization.

33213664 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 779 (or 771 counting only the distinct ones).

The product of its digits is 7776, while the sum is 28.

The square root of 33213664 is about 5763.1297052903. The cubic root of 33213664 is about 321.4442014927. Note that the first 3 decimals are identical.

Adding to 33213664 its reverse (46631233), we get a palindrome (79844897).

Subtracting 33213664 from its reverse (46631233), we obtain a square (13417569 = 3663²).

The spelling of 33213664 in words is "thirty-three million, two hundred thirteen thousand, six hundred sixty-four".