1001201221221 has 64 divisors (see below), whose sum is σ = 1421644234752. Its totient is φ = 625968000000.

The previous prime is 1001201221193. The next prime is 1001201221249. The reversal of 1001201221221 is 1221221021001.

It is an interprime number because it is at equal distance from previous prime (1001201221193) and next prime (1001201221249).

It is not a de Polignac number, because 1001201221221 - 2¹⁹ = 1001200696933 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1001201221221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1001201221271) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 111227721 + ... + 111236721.

It is an arithmetic number, because the mean of its divisors is an integer number (22213191168).

Almost surely, 2^{1001201221221} is an apocalyptic number.

It is an amenable number.

1001201221221 is a deficient number, since it is larger than the sum of its proper divisors (420443013531).

1001201221221 is a wasteful number, since it uses less digits than its factorization.

1001201221221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9434.

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

Adding to 1001201221221 its reverse (1221221021001), we get a palindrome (2222422242222).

The spelling of 1001201221221 in words is "one trillion, one billion, two hundred one million, two hundred twenty-one thousand, two hundred twenty-one".