1221300120100 has 36 divisors (see below), whose sum is σ = 2652934084164. Its totient is φ = 488019988480.

The previous prime is 1221300120071. The next prime is 1221300120113. The reversal of 1221300120100 is 10210031221.

It can be written as a sum of positive squares in 6 ways, for example, as 74297675776 + 1147002444324 = 272576^2 + 1070982^2 .

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, 6152557 + ... + 6347956.

It is an arithmetic number, because the mean of its divisors is an integer number (73692613449).

Almost surely, 2^{1221300120100} is an apocalyptic number.

1221300120100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1221300120100 is an abundant number, since it is smaller than the sum of its proper divisors (1431633964064).

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

1221300120100 is a wasteful number, since it uses less digits than its factorization.

1221300120100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12501504 (or 12501497 counting only the distinct ones).

The product of its (nonzero) digits is 24, while the sum is 13.

Adding to 1221300120100 its reverse (10210031221), we get a palindrome (1231510151321).

The spelling of 1221300120100 in words is "one trillion, two hundred twenty-one billion, three hundred million, one hundred twenty thousand, one hundred".