1221211102100 has 36 divisors (see below), whose sum is σ = 2890939738848. Its totient is φ = 444076764000.

The previous prime is 1221211102081. The next prime is 1221211102121. The reversal of 1221211102100 is 12011121221.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 555094856 + ... + 555097055.

Almost surely, 2^{1221211102100} is an apocalyptic number.

1221211102100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221211102100 is an abundant number, since it is smaller than the sum of its proper divisors (1669728636748).

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

1221211102100 is a wasteful number, since it uses less digits than its factorization.

1221211102100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1110191936 (or 1110191929 counting only the distinct ones).

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

Adding to 1221211102100 its reverse (12011121221), we get a palindrome (1233222223321).

It can be divided in two parts, 122121 and 1102100, that added together give a palindrome (1224221).

The spelling of 1221211102100 in words is "one trillion, two hundred twenty-one billion, two hundred eleven million, one hundred two thousand, one hundred".