1221201010221 has 16 divisors (see below), whose sum is σ = 1641956161536. Its totient is φ = 807314509376.

The previous prime is 1221201010207. The next prime is 1221201010223. The reversal of 1221201010221 is 1220101021221.

It is a cyclic number.

It is not a de Polignac number, because 1221201010221 - 2¹⁹ = 1221200485933 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1221201010221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221201010223) 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, 2873010 + ... + 3270563.

It is an arithmetic number, because the mean of its divisors is an integer number (102622260096).

Almost surely, 2^{1221201010221} is an apocalyptic number.

It is an amenable number.

1221201010221 is a deficient number, since it is larger than the sum of its proper divisors (420755151315).

1221201010221 is a wasteful number, since it uses less digits than its factorization.

1221201010221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6144132.

The product of its (nonzero) digits is 32, while the sum is 15.

Adding to 1221201010221 its reverse (1220101021221), we get a palindrome (2441302031442).

The spelling of 1221201010221 in words is "one trillion, two hundred twenty-one billion, two hundred one million, ten thousand, two hundred twenty-one".