1212211110138 has 128 divisors (see below), whose sum is σ = 2900149518336. Its totient is φ = 330511104000.

The previous prime is 1212211110137. The next prime is 1212211110139. The reversal of 1212211110138 is 8310111122121.

It is an interprime number because it is at equal distance from previous prime (1212211110137) and next prime (1212211110139).

It is not an unprimeable number, because it can be changed into a prime (1212211110137) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 34966113 + ... + 35000763.

It is an arithmetic number, because the mean of its divisors is an integer number (22657418112).

Almost surely, 2^{1212211110138} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1212211110138, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1450074759168).

1212211110138 is an abundant number, since it is smaller than the sum of its proper divisors (1687938408198).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1212211110138 is a wasteful number, since it uses less digits than its factorization.

1212211110138 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 35068.

The product of its (nonzero) digits is 192, while the sum is 24.

Adding to 1212211110138 its reverse (8310111122121), we get a palindrome (9522322232259).

The spelling of 1212211110138 in words is "one trillion, two hundred twelve billion, two hundred eleven million, one hundred ten thousand, one hundred thirty-eight".