221220012100100 has 72 divisors (see below), whose sum is σ = 516991378949640. Its totient is φ = 81678513300480.

The previous prime is 221220012100099. The next prime is 221220012100133. The reversal of 221220012100100 is 1001210022122.

It can be written as a sum of positive squares in 12 ways, for example, as 97048348121344 + 124171663978756 = 9851312^2 + 11143234^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 36399434 + ... + 42039966.

It is an arithmetic number, because the mean of its divisors is an integer number (7180435818745).

Almost surely, 2^{221220012100100} is an apocalyptic number.

221220012100100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221220012100100 is an abundant number, since it is smaller than the sum of its proper divisors (295771366849540).

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

221220012100100 is a wasteful number, since it uses less digits than its factorization.

221220012100100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5670729 (or 5670722 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 221220012100100 its reverse (1001210022122), we get a palindrome (222221222122222).

The spelling of 221220012100100 in words is "two hundred twenty-one trillion, two hundred twenty billion, twelve million, one hundred thousand, one hundred".