1111212121200 has 60 divisors (see below), whose sum is σ = 3559582832088. Its totient is φ = 296323232000.

The previous prime is 1111212121199. The next prime is 1111212121273. The reversal of 1111212121200 is 21212121111.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (60).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1111212121200.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 463003851 + ... + 463006250.

Almost surely, 2^{1111212121200} is an apocalyptic number.

1111212121200 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1111212121200 is an abundant number, since it is smaller than the sum of its proper divisors (2448370710888).

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

1111212121200 is a wasteful number, since it uses less digits than its factorization.

1111212121200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 926010122 (or 926010111 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 15.

Adding to 1111212121200 its reverse (21212121111), we get a palindrome (1132424242311).

It can be divided in two parts, 11 and 11212121200, that added together give a palindrome (11212121211).

The spelling of 1111212121200 in words is "one trillion, one hundred eleven billion, two hundred twelve million, one hundred twenty-one thousand, two hundred".