1220000000221 has 4 divisors (see below), whose sum is σ = 1220002213500. Its totient is φ = 1219997786944.

The previous prime is 1220000000203. The next prime is 1220000000293.

1220000000221 is nontrivially palindromic in base 10.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 544334084100 + 675665916121 = 737790^2 + 821989^2 .

It is a cyclic number.

It is not a de Polignac number, because 1220000000221 - 2¹⁵ = 1219999967453 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1220000000198 and 1220000000207.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1220000000201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 451035 + ... + 1625863.

It is an arithmetic number, because the mean of its divisors is an integer number (305000553375).

Almost surely, 2^{1220000000221} is an apocalyptic number.

It is an amenable number.

1220000000221 is a deficient number, since it is larger than the sum of its proper divisors (2213279).

1220000000221 is a wasteful number, since it uses less digits than its factorization.

1220000000221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2213278.

The product of its (nonzero) digits is 16, while the sum is 10.

It can be divided in two parts, 1220000000 and 221, that added together give a palindrome (1220000221).

The spelling of 1220000000221 in words is "one trillion, two hundred twenty billion, two hundred twenty-one", and thus it is an aban number.