1221010110211 has 4 divisors (see below), whose sum is σ = 1221026255712. Its totient is φ = 1220993964712.

The previous prime is 1221010110181. The next prime is 1221010110233. The reversal of 1221010110211 is 1120110101221.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 1221010110211 - 2²¹ = 1221008013059 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1221010110191 and 1221010110200.

It is not an unprimeable number, because it can be changed into a prime (1221010110311) 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, 7958776 + ... + 8110741.

It is an arithmetic number, because the mean of its divisors is an integer number (305256563928).

Almost surely, 2^{1221010110211} is an apocalyptic number.

1221010110211 is a deficient number, since it is larger than the sum of its proper divisors (16145501).

1221010110211 is an equidigital number, since it uses as much as digits as its factorization.

1221010110211 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16145500.

The product of its (nonzero) digits is 8, while the sum is 13.

Adding to 1221010110211 its reverse (1120110101221), we get a palindrome (2341120211432).

The spelling of 1221010110211 in words is "one trillion, two hundred twenty-one billion, ten million, one hundred ten thousand, two hundred eleven".