1222121111100 has 72 divisors (see below), whose sum is σ = 3631571449968. Its totient is φ = 317090880000.

The previous prime is 1222121111047. The next prime is 1222121111129. The reversal of 1222121111100 is 11111212221.

It is a happy number.

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 1222121111100.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 55039401 + ... + 55061600.

Almost surely, 2^{1222121111100} is an apocalyptic number.

1222121111100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1222121111100 is an abundant number, since it is smaller than the sum of its proper divisors (2409450338868).

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

1222121111100 is a wasteful number, since it uses less digits than its factorization.

1222121111100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 110101055 (or 110101048 counting only the distinct ones).

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

Adding to 1222121111100 its reverse (11111212221), we get a palindrome (1233232323321).

The spelling of 1222121111100 in words is "one trillion, two hundred twenty-two billion, one hundred twenty-one million, one hundred eleven thousand, one hundred".