1211212120100 has 18 divisors (see below), whose sum is σ = 2628330300834. Its totient is φ = 484484848000.

The previous prime is 1211212120051. The next prime is 1211212120117. The reversal of 1211212120100 is 10212121121.

It can be written as a sum of positive squares in 3 ways, for example, as 220454664676 + 990757455424 = 469526^2 + 995368^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 6056060501 + ... + 6056060700.

Almost surely, 2^{1211212120100} is an apocalyptic number.

1211212120100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1211212120100 is an abundant number, since it is smaller than the sum of its proper divisors (1417118180734).

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

1211212120100 is a wasteful number, since it uses less digits than its factorization.

1211212120100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12112121215 (or 12112121208 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 14.

Adding to 1211212120100 its reverse (10212121121), we get a palindrome (1221424241221).

The spelling of 1211212120100 in words is "one trillion, two hundred eleven billion, two hundred twelve million, one hundred twenty thousand, one hundred".