11111221121012 has 6 divisors (see below), whose sum is σ = 19444636961778. Its totient is φ = 5555610560504.

The previous prime is 11111221120973. The next prime is 11111221121023. The reversal of 11111221121012 is 21012112211111.

It can be written as a sum of positive squares in only one way, i.e., 11105996144356 + 5224976656 = 3332566^2 + 72284^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1388902640123 + ... + 1388902640130.

It is an arithmetic number, because the mean of its divisors is an integer number (3240772826963).

Almost surely, 2^{11111221121012} is an apocalyptic number.

It is an amenable number.

11111221121012 is a deficient number, since it is larger than the sum of its proper divisors (8333415840766).

11111221121012 is a wasteful number, since it uses less digits than its factorization.

11111221121012 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2777805280257 (or 2777805280255 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 17.

Adding to 11111221121012 its reverse (21012112211111), we get a palindrome (32123333332123).

The spelling of 11111221121012 in words is "eleven trillion, one hundred eleven billion, two hundred twenty-one million, one hundred twenty-one thousand, twelve".