1221111210011 has 12 divisors (see below), whose sum is σ = 1549610515800. Its totient is φ = 951515228160.

The previous prime is 1221111209957. The next prime is 1221111210047. The reversal of 1221111210011 is 1100121111221.

It is not a de Polignac number, because 1221111210011 - 2⁶ = 1221111209947 is a prime.

It is a super-2 number, since 2×1221111210011² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1221111210611) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1132755686 + ... + 1132756763.

It is an arithmetic number, because the mean of its divisors is an integer number (129134209650).

Almost surely, 2^{1221111210011} is an apocalyptic number.

1221111210011 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1221111210011 is a deficient number, since it is larger than the sum of its proper divisors (328499305789).

1221111210011 is a wasteful number, since it uses less digits than its factorization.

1221111210011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2265512474 (or 2265512467 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 14.

Adding to 1221111210011 its reverse (1100121111221), we get a palindrome (2321232321232).

The spelling of 1221111210011 in words is "one trillion, two hundred twenty-one billion, one hundred eleven million, two hundred ten thousand, eleven".