1212222121 has 16 divisors (see below), whose sum is σ = 1345154688. Its totient is φ = 1083174400.

The previous prime is 1212222091. The next prime is 1212222133.

It is a happy number.

1212222121 is nontrivially palindromic in base 10.

It is not a de Polignac number, because 1212222121 - 2¹¹ = 1212220073 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1212222095 and 1212222104.

It is not an unprimeable number, because it can be changed into a prime (1212222181) 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, 273495 + ... + 277891.

It is an arithmetic number, because the mean of its divisors is an integer number (84072168).

Almost surely, 2^1212222121 is an apocalyptic number.

1212222121 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

1212222121 is a deficient number, since it is larger than the sum of its proper divisors (132932567).

1212222121 is a wasteful number, since it uses less digits than its factorization.

1212222121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4832.

The product of its digits is 64, while the sum is 16.

The square root of 1212222121 is about 34816.9803544190. The cubic root of 1212222121 is about 1066.2541511099.

It can be divided in two parts, 12122 and 22121, that added together give a palindrome (34243).

The spelling of 1212222121 in words is "one billion, two hundred twelve million, two hundred twenty-two thousand, one hundred twenty-one".