21231320100000 has 576 divisors, whose sum is σ = 73455818526720. Its totient is φ = 5354294400000.

The previous prime is 21231320099993. The next prime is 21231320100007. The reversal of 21231320100000 is 102313212.

It is an interprime number because it is at equal distance from previous prime (21231320099993) and next prime (21231320100007).

It is a Harshad number since it is a multiple of its sum of digits (15).

It is not an unprimeable number, because it can be changed into a prime (21231320100007) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 3596697049 + ... + 3596702951.

It is an arithmetic number, because the mean of its divisors is an integer number (127527462720).

Almost surely, 2^{21231320100000} is an apocalyptic number.

21231320100000 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 21231320100000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36727909263360).

21231320100000 is an abundant number, since it is smaller than the sum of its proper divisors (52224498426720).

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

21231320100000 is an equidigital number, since it uses as much as digits as its factorization.

21231320100000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6591 (or 6563 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21231320100000 its reverse (102313212), we get a palindrome (21231422413212).

The spelling of 21231320100000 in words is "twenty-one trillion, two hundred thirty-one billion, three hundred twenty million, one hundred thousand".