221232768 has 128 divisors (see below), whose sum is σ = 630702720. Its totient is φ = 68530176.

The previous prime is 221232701. The next prime is 221232769. The reversal of 221232768 is 867232122.

It is a tau number, because it is divible by the number of its divisors (128).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221232769) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 326446 + ... + 327122.

It is an arithmetic number, because the mean of its divisors is an integer number (4927365).

Almost surely, 2^221232768 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 221232768, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (315351360).

221232768 is an abundant number, since it is smaller than the sum of its proper divisors (409469952).

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

221232768 is a wasteful number, since it uses less digits than its factorization.

221232768 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 754 (or 742 counting only the distinct ones).

The product of its digits is 16128, while the sum is 33.

The square root of 221232768 is about 14873.8955220211. The cubic root of 221232768 is about 604.8065478981.

It can be divided in two parts, 2212 and 32768, that added together give a triangular number (34980 = T₂₆₄).

The spelling of 221232768 in words is "two hundred twenty-one million, two hundred thirty-two thousand, seven hundred sixty-eight".