10421121221 has 32 divisors (see below), whose sum is σ = 12536045568. Its totient is φ = 8469901440.

The previous prime is 10421121211. The next prime is 10421121257. The reversal of 10421121221 is 12212112401.

It is a de Polignac number, because none of the positive numbers 2^k-10421121221 is a prime.

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 10421121221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10421121211) 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, 11438756 + ... + 11439666.

It is an arithmetic number, because the mean of its divisors is an integer number (391751424).

Almost surely, 2^10421121221 is an apocalyptic number.

It is an amenable number.

10421121221 is a deficient number, since it is larger than the sum of its proper divisors (2114924347).

10421121221 is a wasteful number, since it uses less digits than its factorization.

10421121221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1481.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 10421121221 its reverse (12212112401), we get a palindrome (22633233622).

The spelling of 10421121221 in words is "ten billion, four hundred twenty-one million, one hundred twenty-one thousand, two hundred twenty-one".