210121221121 has 16 divisors (see below), whose sum is σ = 248985158400. Its totient is φ = 173497238208.

The previous prime is 210121221061. The next prime is 210121221137. The reversal of 210121221121 is 121122121012.

It is not a de Polignac number, because 210121221121 - 2¹¹ = 210121219073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 210121221095 and 210121221104.

It is not an unprimeable number, because it can be changed into a prime (210121221721) 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, 1089790 + ... + 1268023.

It is an arithmetic number, because the mean of its divisors is an integer number (15561572400).

Almost surely, 2^210121221121 is an apocalyptic number.

It is an amenable number.

210121221121 is a deficient number, since it is larger than the sum of its proper divisors (38863937279).

210121221121 is a wasteful number, since it uses less digits than its factorization.

210121221121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2358288.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 210121221121 its reverse (121122121012), we get a palindrome (331243342133).

The spelling of 210121221121 in words is "two hundred ten billion, one hundred twenty-one million, two hundred twenty-one thousand, one hundred twenty-one".