1221222012221 has 8 divisors (see below), whose sum is σ = 1275071360640. Its totient is φ = 1167435392112.

The previous prime is 1221222012211. The next prime is 1221222012251. The reversal of 1221222012221 is 1222102221221.

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 1221222012221 - 2¹⁴ = 1221221995837 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221222012193 and 1221222012202.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221222012211) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 15642281 + ... + 15720158.

It is an arithmetic number, because the mean of its divisors is an integer number (159383920080).

Almost surely, 2^{1221222012221} is an apocalyptic number.

It is an amenable number.

1221222012221 is a deficient number, since it is larger than the sum of its proper divisors (53849348419).

1221222012221 is a wasteful number, since it uses less digits than its factorization.

1221222012221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31364155.

The product of its (nonzero) digits is 256, while the sum is 20.

Adding to 1221222012221 its reverse (1222102221221), we get a palindrome (2443324233442).

The spelling of 1221222012221 in words is "one trillion, two hundred twenty-one billion, two hundred twenty-two million, twelve thousand, two hundred twenty-one".