11211202121 has 4 divisors (see below), whose sum is σ = 12812802432. Its totient is φ = 9609601812.

The previous prime is 11211202099. The next prime is 11211202157. The reversal of 11211202121 is 12120211211.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 12120211211 = 43 ⋅281865377.

It is a cyclic number.

It is not a de Polignac number, because 11211202121 - 2²² = 11207007817 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11211202096 and 11211202105.

It is not an unprimeable number, because it can be changed into a prime (11211202621) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 800800145 + ... + 800800158.

It is an arithmetic number, because the mean of its divisors is an integer number (3203200608).

Almost surely, 2^11211202121 is an apocalyptic number.

It is an amenable number.

11211202121 is a deficient number, since it is larger than the sum of its proper divisors (1601600311).

11211202121 is an equidigital number, since it uses as much as digits as its factorization.

11211202121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1601600310.

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 11211202121 its reverse (12120211211), we get a palindrome (23331413332).

The spelling of 11211202121 in words is "eleven billion, two hundred eleven million, two hundred two thousand, one hundred twenty-one".