1221112122100 has 36 divisors (see below), whose sum is σ = 2853645100684. Its totient is φ = 450872167680.

The previous prime is 1221112122077. The next prime is 1221112122103. The reversal of 1221112122100 is 12212111221.

It can be written as a sum of positive squares in 6 ways, for example, as 465391382416 + 755720739684 = 682196^2 + 869322^2 .

It is a super-2 number, since 2×1221112122100² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1221112122103) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 469657209 + ... + 469659808.

Almost surely, 2^{1221112122100} is an apocalyptic number.

1221112122100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221112122100 is an abundant number, since it is smaller than the sum of its proper divisors (1632532978584).

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

1221112122100 is a wasteful number, since it uses less digits than its factorization.

1221112122100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 939317044 (or 939317037 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 1221112122100 its reverse (12212111221), we get a palindrome (1233324233321).

It can be divided in two parts, 12211121 and 22100, that added together give a palindrome (12233221).

The spelling of 1221112122100 in words is "one trillion, two hundred twenty-one billion, one hundred twelve million, one hundred twenty-two thousand, one hundred".