1212212111 has 4 divisors (see below), whose sum is σ = 1322413224. Its totient is φ = 1102011000.

The previous prime is 1212212101. The next prime is 1212212119. The reversal of 1212212111 is 1112122121.

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 1212212111 - 2¹⁸ = 1211949967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1212212119) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55100540 + ... + 55100561.

It is an arithmetic number, because the mean of its divisors is an integer number (330603306).

Almost surely, 2^1212212111 is an apocalyptic number.

1212212111 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1212212111 is a deficient number, since it is larger than the sum of its proper divisors (110201113).

1212212111 is a wasteful number, since it uses less digits than its factorization.

1212212111 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110201112.

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

The square root of 1212212111 is about 34816.8366024256. The cubic root of 1212212111 is about 1066.2512162150.

Adding to 1212212111 its reverse (1112122121), we get a palindrome (2324334232).

It can be divided in two parts, 12122121 and 11, that multiplied together give a palindrome (133343331).

The spelling of 1212212111 in words is "one billion, two hundred twelve million, two hundred twelve thousand, one hundred eleven".