2001231223320 has 512 divisors, whose sum is σ = 7131933388800. Its totient is φ = 439710031872.

The previous prime is 2001231223307. The next prime is 2001231223391. The reversal of 2001231223320 is 233221321002.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 1649819034 + ... + 1649820246.

It is an arithmetic number, because the mean of its divisors is an integer number (13929557400).

Almost surely, 2^{2001231223320} is an apocalyptic number.

2001231223320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 2001231223320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3565966694400).

2001231223320 is an abundant number, since it is smaller than the sum of its proper divisors (5130702165480).

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

2001231223320 is a wasteful number, since it uses less digits than its factorization.

2001231223320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1867 (or 1863 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 2001231223320 its reverse (233221321002), we get a palindrome (2234452544322).

The spelling of 2001231223320 in words is "two trillion, one billion, two hundred thirty-one million, two hundred twenty-three thousand, three hundred twenty".