1220221001221 has 16 divisors (see below), whose sum is σ = 1328796475200. Its totient is φ = 1116084590208.

The previous prime is 1220221001171. The next prime is 1220221001249. The reversal of 1220221001221 is 1221001220221.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 1220221001221 - 2¹⁷ = 1220220870149 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220221001195 and 1220221001204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220221005221) 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, 16568746 + ... + 16642228.

It is an arithmetic number, because the mean of its divisors is an integer number (83049779700).

Almost surely, 2^{1220221001221} is an apocalyptic number.

It is an amenable number.

1220221001221 is a deficient number, since it is larger than the sum of its proper divisors (108575473979).

1220221001221 is a wasteful number, since it uses less digits than its factorization.

1220221001221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 103668.

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 1220221001221 its reverse (1221001220221), we get a palindrome (2441222221442).

The spelling of 1220221001221 in words is "one trillion, two hundred twenty billion, two hundred twenty-one million, one thousand, two hundred twenty-one".