221429824 has 140 divisors (see below), whose sum is σ = 563471568. Its totient is φ = 85612800.

The previous prime is 221429821. The next prime is 221429827. The reversal of 221429824 is 428924122.

It is an interprime number because it is at equal distance from previous prime (221429821) and next prime (221429827).

It is a self number, because there is not a number n which added to its sum of digits gives 221429824.

It is not an unprimeable number, because it can be changed into a prime (221429821) by changing a digit.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 1690239 + ... + 1690369.

Almost surely, 2^221429824 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 221429824, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (281735784).

221429824 is an abundant number, since it is smaller than the sum of its proper divisors (342041744).

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

221429824 is an equidigital number, since it uses as much as digits as its factorization.

221429824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182 (or 151 counting only the distinct ones).

The product of its digits is 18432, while the sum is 34.

The square root of 221429824 is about 14880.5182705442. The cubic root of 221429824 is about 604.9860652939.

The spelling of 221429824 in words is "two hundred twenty-one million, four hundred twenty-nine thousand, eight hundred twenty-four".