221221305215 has 8 divisors (see below), whose sum is σ = 272640311520. Its totient is φ = 172193880672.

The previous prime is 221221305199. The next prime is 221221305233. The reversal of 221221305215 is 512503122122.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 221221305215 - 2⁴ = 221221305199 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 597895235 + ... + 597895604.

It is an arithmetic number, because the mean of its divisors is an integer number (34080038940).

Almost surely, 2^221221305215 is an apocalyptic number.

221221305215 is a deficient number, since it is larger than the sum of its proper divisors (51419006305).

221221305215 is a wasteful number, since it uses less digits than its factorization.

221221305215 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1195790881.

The product of its (nonzero) digits is 2400, while the sum is 26.

Adding to 221221305215 its reverse (512503122122), we get a palindrome (733724427337).

The spelling of 221221305215 in words is "two hundred twenty-one billion, two hundred twenty-one million, three hundred five thousand, two hundred fifteen".