21311232320320 has 28 divisors (see below), whose sum is σ = 50747371963524. Its totient is φ = 8524492928000.

The previous prime is 21311232320239. The next prime is 21311232320341. The reversal of 21311232320320 is 2302323211312.

It can be written as a sum of positive squares in 2 ways, for example, as 2143787932224 + 19167444388096 = 1464168^2 + 4378064^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 33298800181 + ... + 33298800820.

Almost surely, 2^{21311232320320} is an apocalyptic number.

21311232320320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21311232320320 is an abundant number, since it is smaller than the sum of its proper divisors (29436139643204).

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

21311232320320 is an equidigital number, since it uses as much as digits as its factorization.

21311232320320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66597601018 (or 66597601008 counting only the distinct ones).

The product of its (nonzero) digits is 2592, while the sum is 25.

Adding to 21311232320320 its reverse (2302323211312), we get a palindrome (23613555531632).

The spelling of 21311232320320 in words is "twenty-one trillion, three hundred eleven billion, two hundred thirty-two million, three hundred twenty thousand, three hundred twenty".