221221413 has 24 divisors (see below), whose sum is σ = 365591616. Its totient is φ = 126273600.

The previous prime is 221221397. The next prime is 221221421. The reversal of 221221413 is 314122122.

It is a happy number.

221221413 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 221221413 - 2⁴ = 221221397 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221221423) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 92118 + ... + 94488.

It is an arithmetic number, because the mean of its divisors is an integer number (15232984).

Almost surely, 2^221221413 is an apocalyptic number.

It is an amenable number.

221221413 is a deficient number, since it is larger than the sum of its proper divisors (144370203).

221221413 is a wasteful number, since it uses less digits than its factorization.

221221413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3865 (or 3862 counting only the distinct ones).

The product of its digits is 192, while the sum is 18.

The square root of 221221413 is about 14873.5138081087. The cubic root of 221221413 is about 604.7962002811.

Adding to 221221413 its reverse (314122122), we get a palindrome (535343535).

The spelling of 221221413 in words is "two hundred twenty-one million, two hundred twenty-one thousand, four hundred thirteen".