2001863221 has 4 divisors (see below), whose sum is σ = 2002593132. Its totient is φ = 2001133312.

The previous prime is 2001863209. The next prime is 2001863231. The reversal of 2001863221 is 1223681002.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1529670321 + 472192900 = 39111^2 + 21730^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-2001863221 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001863231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 360826 + ... + 366331.

It is an arithmetic number, because the mean of its divisors is an integer number (500648283).

Almost surely, 2^2001863221 is an apocalyptic number.

It is an amenable number.

2001863221 is a deficient number, since it is larger than the sum of its proper divisors (729911).

2001863221 is an equidigital number, since it uses as much as digits as its factorization.

2001863221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 729910.

The product of its (nonzero) digits is 1152, while the sum is 25.

The square root of 2001863221 is about 44742.1861446219. The cubic root of 2001863221 is about 1260.3121803527.

The spelling of 2001863221 in words is "two billion, one million, eight hundred sixty-three thousand, two hundred twenty-one".