1221322401221 has 8 divisors (see below), whose sum is σ = 1315551444480. Its totient is φ = 1127133524592.

The previous prime is 1221322401113. The next prime is 1221322401227. The reversal of 1221322401221 is 1221042231221.

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 1221322401221 - 2³⁸ = 946444494277 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221322401227) 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, 9978485 + ... + 10100138.

It is an arithmetic number, because the mean of its divisors is an integer number (164443930560).

Almost surely, 2^{1221322401221} is an apocalyptic number.

It is an amenable number.

1221322401221 is a deficient number, since it is larger than the sum of its proper divisors (94229043259).

1221322401221 is a wasteful number, since it uses less digits than its factorization.

1221322401221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20083315.

The product of its (nonzero) digits is 768, while the sum is 23.

Adding to 1221322401221 its reverse (1221042231221), we get a palindrome (2442364632442).

The spelling of 1221322401221 in words is "one trillion, two hundred twenty-one billion, three hundred twenty-two million, four hundred one thousand, two hundred twenty-one".