2001221212100 has 72 divisors (see below), whose sum is σ = 4737855695328. Its totient is φ = 727652396800.

The previous prime is 2001221212099. The next prime is 2001221212117. The reversal of 2001221212100 is 12121221002.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 13375304 + ... + 13524096.

It is an arithmetic number, because the mean of its divisors is an integer number (65803551324).

Almost surely, 2^{2001221212100} is an apocalyptic number.

2001221212100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001221212100 is an abundant number, since it is smaller than the sum of its proper divisors (2736634483228).

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

2001221212100 is a wasteful number, since it uses less digits than its factorization.

2001221212100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161045 (or 161038 counting only the distinct ones).

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

Adding to 2001221212100 its reverse (12121221002), we get a palindrome (2013342433102).

The spelling of 2001221212100 in words is "two trillion, one billion, two hundred twenty-one million, two hundred twelve thousand, one hundred".