2001221201000 has 96 divisors (see below), whose sum is σ = 5447405925000. Its totient is φ = 686132966400.

The previous prime is 2001221200999. The next prime is 2001221201017. The reversal of 2001221201000 is 1021221002.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 73972032484 + 1927249168516 = 271978^2 + 1388254^2 .

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, 20371625 + ... + 20469624.

Almost surely, 2^{2001221201000} is an apocalyptic number.

2001221201000 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001221201000 is an abundant number, since it is smaller than the sum of its proper divisors (3446184724000).

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

2001221201000 is a wasteful number, since it uses less digits than its factorization.

2001221201000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 40841284 (or 40841263 counting only the distinct ones).

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

Adding to 2001221201000 its reverse (1021221002), we get a palindrome (2002242422002).

The spelling of 2001221201000 in words is "two trillion, one billion, two hundred twenty-one million, two hundred one thousand".