21000031120000 has 160 divisors (see below), whose sum is σ = 52611279017220. Its totient is φ = 8346504192000.

The previous prime is 21000031119989. The next prime is 21000031120009. The reversal of 21000031120000 is 2113000012.

It can be written as a sum of positive squares in 10 ways, for example, as 7912248888384 + 13087782231616 = 2812872^2 + 3617704^2 .

It is a tau number, because it is divible by the number of its divisors (160).

It is a Harshad number since it is a multiple of its sum of digits (10).

It is not an unprimeable number, because it can be changed into a prime (21000031120009) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 11724012 + ... + 13395988.

Almost surely, 2^{21000031120000} is an apocalyptic number.

21000031120000 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 21000031120000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26305639508610).

21000031120000 is an abundant number, since it is smaller than the sum of its proper divisors (31611247897220).

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

21000031120000 is an equidigital number, since it uses as much as digits as its factorization.

21000031120000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1672168 (or 1672141 counting only the distinct ones).

The product of its (nonzero) digits is 12, while the sum is 10.

Adding to 21000031120000 its reverse (2113000012), we get a palindrome (21002144120012).

The spelling of 21000031120000 in words is "twenty-one trillion, thirty-one million, one hundred twenty thousand".