1211220012111 has 16 divisors (see below), whose sum is σ = 1730720961024. Its totient is φ = 751497256224.

The previous prime is 1211220012103. The next prime is 1211220012131. The reversal of 1211220012111 is 1112100221121.

It is a happy number.

It is not a de Polignac number, because 1211220012111 - 2³ = 1211220012103 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1211220012131) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 237212491 + ... + 237217596.

It is an arithmetic number, because the mean of its divisors is an integer number (108170060064).

Almost surely, 2^{1211220012111} is an apocalyptic number.

1211220012111 is a deficient number, since it is larger than the sum of its proper divisors (519500948913).

1211220012111 is a wasteful number, since it uses less digits than its factorization.

1211220012111 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 474430150.

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1211220012111 its reverse (1112100221121), we get a palindrome (2323320233232).

The spelling of 1211220012111 in words is "one trillion, two hundred eleven billion, two hundred twenty million, twelve thousand, one hundred eleven".