21312231000000 has 392 divisors, whose sum is σ = 71537549307648. Its totient is φ = 5598384000000.

The previous prime is 21312230999987. The next prime is 21312231000001. The reversal of 21312231000000 is 13221312.

It is a super-2 number, since 2×21312231000000² (a number of 27 digits) contains 22 as substring.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21312231000001) by changing a digit.

It is a polite number, since it can be written in 55 ways as a sum of consecutive naturals, for example, 200946985 + ... + 201053015.

Almost surely, 2^{21312231000000} is an apocalyptic number.

21312231000000 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 21312231000000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (35768774653824).

21312231000000 is an abundant number, since it is smaller than the sum of its proper divisors (50225318307648).

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

21312231000000 is an frugal number, since it uses more digits than its factorization.

21312231000000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106143 (or 106108 counting only the distinct ones).

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

Adding to 21312231000000 its reverse (13221312), we get a palindrome (21312244221312).

The spelling of 21312231000000 in words is "twenty-one trillion, three hundred twelve billion, two hundred thirty-one million", and thus it is an aban number.