1201221111021 has 64 divisors (see below), whose sum is σ = 1748322385920. Its totient is φ = 731499690240.

The previous prime is 1201221111011. The next prime is 1201221111043. The reversal of 1201221111021 is 1201111221021.

It is a happy number.

It is not a de Polignac number, because 1201221111021 - 2¹¹ = 1201221108973 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1201221111011) 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, 74588056 + ... + 74604158.

It is an arithmetic number, because the mean of its divisors is an integer number (27317537280).

Almost surely, 2^{1201221111021} is an apocalyptic number.

It is an amenable number.

1201221111021 is a deficient number, since it is larger than the sum of its proper divisors (547101274899).

1201221111021 is a wasteful number, since it uses less digits than its factorization.

1201221111021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16706.

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

Adding to 1201221111021 its reverse (1201111221021), we get a palindrome (2402332332042).

The spelling of 1201221111021 in words is "one trillion, two hundred one billion, two hundred twenty-one million, one hundred eleven thousand, twenty-one".