2001355221 has 32 divisors (see below), whose sum is σ = 2799820800. Its totient is φ = 1270019520.

The previous prime is 2001355217. The next prime is 2001355229. The reversal of 2001355221 is 1225531002.

It is not a de Polignac number, because 2001355221 - 2² = 2001355217 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001355229) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2019036 + ... + 2020026.

It is an arithmetic number, because the mean of its divisors is an integer number (87494400).

Almost surely, 2^2001355221 is an apocalyptic number.

It is an amenable number.

2001355221 is a deficient number, since it is larger than the sum of its proper divisors (798465579).

2001355221 is a wasteful number, since it uses less digits than its factorization.

2001355221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1329.

The product of its (nonzero) digits is 600, while the sum is 21.

The square root of 2001355221 is about 44736.5088155077. The cubic root of 2001355221 is about 1260.2055642188.

Adding to 2001355221 its reverse (1225531002), we get a palindrome (3226886223).

The spelling of 2001355221 in words is "two billion, one million, three hundred fifty-five thousand, two hundred twenty-one".