10001221211 has 4 divisors (see below), whose sum is σ = 10189923552. Its totient is φ = 9812518872.

The previous prime is 10001221201. The next prime is 10001221229. The reversal of 10001221211 is 11212210001.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-10001221211 is a prime.

It is a super-2 number, since 2×10001221211² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 10001221192 and 10001221201.

It is not an unprimeable number, because it can be changed into a prime (10001221201) 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, 94351091 + ... + 94351196.

It is an arithmetic number, because the mean of its divisors is an integer number (2547480888).

Almost surely, 2^10001221211 is an apocalyptic number.

10001221211 is a deficient number, since it is larger than the sum of its proper divisors (188702341).

10001221211 is an equidigital number, since it uses as much as digits as its factorization.

10001221211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 188702340.

The product of its (nonzero) digits is 8, while the sum is 11.

Adding to 10001221211 its reverse (11212210001), we get a palindrome (21213431212).

The spelling of 10001221211 in words is "ten billion, one million, two hundred twenty-one thousand, two hundred eleven".