221240444 has 12 divisors (see below), whose sum is σ = 394476264. Its totient is φ = 108532944.

The previous prime is 221240441. The next prime is 221240447. The reversal of 221240444 is 444042122.

It is an interprime number because it is at equal distance from previous prime (221240441) and next prime (221240447).

It is a super-2 number, since 2×221240444² = 97894668122634272, which contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221240441) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 521582 + ... + 522005.

It is an arithmetic number, because the mean of its divisors is an integer number (32873022).

Almost surely, 2^221240444 is an apocalyptic number.

It is an amenable number.

221240444 is a deficient number, since it is larger than the sum of its proper divisors (173235820).

221240444 is a wasteful number, since it uses less digits than its factorization.

221240444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1043644 (or 1043642 counting only the distinct ones).

The product of its (nonzero) digits is 2048, while the sum is 23.

The square root of 221240444 is about 14874.1535557490. The cubic root of 221240444 is about 604.8135427048.

Adding to 221240444 its reverse (444042122), we get a palindrome (665282566).

The spelling of 221240444 in words is "two hundred twenty-one million, two hundred forty thousand, four hundred forty-four".