2001012321 has 32 divisors (see below), whose sum is σ = 3360688128. Its totient is φ = 1028759040.

The previous prime is 2001012313. The next prime is 2001012347. The reversal of 2001012321 is 1232101002.

It is not a de Polignac number, because 2001012321 - 2³ = 2001012313 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2001012297 and 2001012306.

It is not an unprimeable number, because it can be changed into a prime (2001012361) 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, 22245 + ... + 67058.

It is an arithmetic number, because the mean of its divisors is an integer number (105021504).

Almost surely, 2^2001012321 is an apocalyptic number.

2001012321 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

2001012321 is a deficient number, since it is larger than the sum of its proper divisors (1359675807).

2001012321 is a wasteful number, since it uses less digits than its factorization.

2001012321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 89421.

The product of its (nonzero) digits is 24, while the sum is 12.

The square root of 2001012321 is about 44732.6762110205. The cubic root of 2001012321 is about 1260.1335881289.

Adding to 2001012321 its reverse (1232101002), we get a palindrome (3233113323).

The spelling of 2001012321 in words is "two billion, one million, twelve thousand, three hundred twenty-one".