1221100122011 has 64 divisors (see below), whose sum is σ = 1591704898560. Its totient is φ = 908920320000.

The previous prime is 1221100122001. The next prime is 1221100122013. The reversal of 1221100122011 is 1102210011221.

It is not a de Polignac number, because 1221100122011 - 2¹⁸ = 1221099859867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1221100122013) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 210495311 + ... + 210501111.

It is an arithmetic number, because the mean of its divisors is an integer number (24870389040).

Almost surely, 2^{1221100122011} is an apocalyptic number.

1221100122011 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221100122011 is a deficient number, since it is larger than the sum of its proper divisors (370604776549).

1221100122011 is a wasteful number, since it uses less digits than its factorization.

1221100122011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6836.

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

Adding to 1221100122011 its reverse (1102210011221), we get a palindrome (2323310133232).

The spelling of 1221100122011 in words is "one trillion, two hundred twenty-one billion, one hundred million, one hundred twenty-two thousand, eleven".