1212111113 has 4 divisors (see below), whose sum is σ = 1234981188. Its totient is φ = 1189241040.

The previous prime is 1212111097. The next prime is 1212111119. The reversal of 1212111113 is 3111112121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 3111112121 = 13 ⋅239316317.

It can be written as a sum of positive squares in 2 ways, for example, as 550747024 + 661364089 = 23468^2 + 25717^2 .

It is a cyclic number.

It is not a de Polignac number, because 1212111113 - 2⁴ = 1212111097 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1212111119) 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, 11434958 + ... + 11435063.

It is an arithmetic number, because the mean of its divisors is an integer number (308745297).

Almost surely, 2^1212111113 is an apocalyptic number.

It is an amenable number.

1212111113 is a deficient number, since it is larger than the sum of its proper divisors (22870075).

1212111113 is an equidigital number, since it uses as much as digits as its factorization.

1212111113 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 22870074.

The product of its digits is 12, while the sum is 14.

The square root of 1212111113 is about 34815.3861532513. The cubic root of 1212111113 is about 1066.2216030722.

Adding to 1212111113 its reverse (3111112121), we get a palindrome (4323223234).

The spelling of 1212111113 in words is "one billion, two hundred twelve million, one hundred eleven thousand, one hundred thirteen".