2001220012100 has 36 divisors (see below), whose sum is σ = 4349422366548. Its totient is φ = 799239168000.

The previous prime is 2001220012079. The next prime is 2001220012111. The reversal of 2001220012100 is 12100221002.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 1167862276 + 2000052149824 = 34174^2 + 1414232^2 .

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, 15546041 + ... + 15674240.

Almost surely, 2^{2001220012100} is an apocalyptic number.

2001220012100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001220012100 is an abundant number, since it is smaller than the sum of its proper divisors (2348202354448).

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

2001220012100 is a wasteful number, since it uses less digits than its factorization.

2001220012100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31220936 (or 31220929 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 11.

Adding to 2001220012100 its reverse (12100221002), we get a palindrome (2013320233102).

The spelling of 2001220012100 in words is "two trillion, one billion, two hundred twenty million, twelve thousand, one hundred".