221284830 has 64 divisors (see below), whose sum is σ = 602058240. Its totient is φ = 51601536.

The previous prime is 221284823. The next prime is 221284841. The reversal of 221284830 is 38482122.

221284830 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a Harshad number since it is a multiple of its sum of digits (30).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 7522 + ... + 22341.

It is an arithmetic number, because the mean of its divisors is an integer number (9407160).

Almost surely, 2^221284830 is an apocalyptic number.

221284830 is an abundant number, since it is smaller than the sum of its proper divisors (380773410).

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

221284830 is a wasteful number, since it uses less digits than its factorization.

221284830 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 29905.

The product of its (nonzero) digits is 6144, while the sum is 30.

The square root of 221284830 is about 14875.6455322114. The cubic root of 221284830 is about 604.8539865742.

The spelling of 221284830 in words is "two hundred twenty-one million, two hundred eighty-four thousand, eight hundred thirty".