1211110021111 has 4 divisors (see below), whose sum is σ = 1211813747424. Its totient is φ = 1210406294800.

The previous prime is 1211110021103. The next prime is 1211110021153. The reversal of 1211110021111 is 1111200111121.

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 1211110021111 - 2³ = 1211110021103 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1211110021091 and 1211110021100.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211110021211) 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, 351860575 + ... + 351864016.

It is an arithmetic number, because the mean of its divisors is an integer number (302953436856).

Almost surely, 2^{1211110021111} is an apocalyptic number.

1211110021111 is a deficient number, since it is larger than the sum of its proper divisors (703726313).

1211110021111 is an equidigital number, since it uses as much as digits as its factorization.

1211110021111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 703726312.

The product of its (nonzero) digits is 4, while the sum is 13.

Adding to 1211110021111 its reverse (1111200111121), we get a palindrome (2322310132232).

The spelling of 1211110021111 in words is "one trillion, two hundred eleven billion, one hundred ten million, twenty-one thousand, one hundred eleven".