221224140 has 36 divisors (see below), whose sum is σ = 671047104. Its totient is φ = 58993056.

The previous prime is 221224139. The next prime is 221224169. The reversal of 221224140 is 41422122.

It is a tau number, because it is divible by the number of its divisors (36).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 614332 + ... + 614691.

Almost surely, 2^221224140 is an apocalyptic number.

221224140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221224140 is an abundant number, since it is smaller than the sum of its proper divisors (449822964).

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

221224140 is a wasteful number, since it uses less digits than its factorization.

221224140 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1229038 (or 1229033 counting only the distinct ones).

The product of its (nonzero) digits is 256, while the sum is 18.

The square root of 221224140 is about 14873.6054808510. The cubic root of 221224140 is about 604.7986853818.

Adding to 221224140 its reverse (41422122), we get a palindrome (262646262).

It can be divided in two parts, 22122 and 4140, that added together give a palindrome (26262).

The spelling of 221224140 in words is "two hundred twenty-one million, two hundred twenty-four thousand, one hundred forty".