221334520 has 64 divisors (see below), whose sum is σ = 566922240. Its totient is φ = 76982400.

The previous prime is 221334517. The next prime is 221334521. The reversal of 221334520 is 25433122.

It is a Harshad number since it is a multiple of its sum of digits (22).

It is a junction number, because it is equal to n+sod(n) for n = 221334491 and 221334500.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221334521) 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, 816 + ... + 21055.

It is an arithmetic number, because the mean of its divisors is an integer number (8858160).

Almost surely, 2^221334520 is an apocalyptic number.

221334520 is a gapful number since it is divisible by the number (20) 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 221334520, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (283461120).

221334520 is an abundant number, since it is smaller than the sum of its proper divisors (345587720).

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

221334520 is a wasteful number, since it uses less digits than its factorization.

221334520 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21916 (or 21912 counting only the distinct ones).

The product of its (nonzero) digits is 1440, while the sum is 22.

The square root of 221334520 is about 14877.3156180811. The cubic root of 221334520 is about 604.8992569545.

Adding to 221334520 its reverse (25433122), we get a palindrome (246767642).

The spelling of 221334520 in words is "two hundred twenty-one million, three hundred thirty-four thousand, five hundred twenty".