201221121022021 has 8 divisors (see below), whose sum is σ = 203645939361984. Its totient is φ = 198796313812800.

The previous prime is 201221121021971. The next prime is 201221121022037. The reversal of 201221121022021 is 120220121122102.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 201221121022021 - 2³⁵ = 201186761283653 is a prime.

It is a super-2 number, since 2×201221121022021² (a number of 29 digits) contains 22 as substring.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 201221121022021.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (201221121022921) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 36996840 + ... + 42085726.

It is an arithmetic number, because the mean of its divisors is an integer number (25455742420248).

Almost surely, 2^{201221121022021} is an apocalyptic number.

It is an amenable number.

201221121022021 is a deficient number, since it is larger than the sum of its proper divisors (2424818339963).

201221121022021 is an equidigital number, since it uses as much as digits as its factorization.

201221121022021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5565371.

The product of its (nonzero) digits is 128, while the sum is 19.

Adding to 201221121022021 its reverse (120220121122102), we get a palindrome (321441242144123).

The spelling of 201221121022021 in words is "two hundred one trillion, two hundred twenty-one billion, one hundred twenty-one million, twenty-two thousand, twenty-one".