1011211201221 has 32 divisors (see below), whose sum is σ = 1469711093760. Its totient is φ = 614733525504.

The previous prime is 1011211201213. The next prime is 1011211201241. The reversal of 1011211201221 is 1221021121101.

It is a happy number.

It is not a de Polignac number, because 1011211201221 - 2³ = 1011211201213 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1011211201221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011211201241) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 715935 + ... + 1592163.

It is an arithmetic number, because the mean of its divisors is an integer number (45928471680).

Almost surely, 2^{1011211201221} is an apocalyptic number.

It is an amenable number.

1011211201221 is a deficient number, since it is larger than the sum of its proper divisors (458499892539).

1011211201221 is a wasteful number, since it uses less digits than its factorization.

1011211201221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 876605.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1011211201221 its reverse (1221021121101), we get a palindrome (2232232322322).

The spelling of 1011211201221 in words is "one trillion, eleven billion, two hundred eleven million, two hundred one thousand, two hundred twenty-one".