221242413 has 16 divisors (see below), whose sum is σ = 337339520. Its totient is φ = 126346176.

The previous prime is 221242409. The next prime is 221242433. The reversal of 221242413 is 314242122.

It is not a de Polignac number, because 221242413 - 2² = 221242409 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a self number, because there is not a number n which added to its sum of digits gives 221242413.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221242433) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 62043 + ... + 65511.

It is an arithmetic number, because the mean of its divisors is an integer number (21083720).

Almost surely, 2^221242413 is an apocalyptic number.

It is an amenable number.

221242413 is a deficient number, since it is larger than the sum of its proper divisors (116097107).

221242413 is a wasteful number, since it uses less digits than its factorization.

221242413 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6516.

The product of its digits is 768, while the sum is 21.

The square root of 221242413 is about 14874.2197442420. The cubic root of 221242413 is about 604.8153369433.

Adding to 221242413 its reverse (314242122), we get a palindrome (535484535).

The spelling of 221242413 in words is "two hundred twenty-one million, two hundred forty-two thousand, four hundred thirteen".