21000031302331 has 4 divisors (see below), whose sum is σ = 21009830665792. Its totient is φ = 20990231938872.

The previous prime is 21000031302319. The next prime is 21000031302361. The reversal of 21000031302331 is 13320313000012.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 21000031302331 - 2⁷ = 21000031302203 is a prime.

It is a super-2 number, since 2×21000031302331² (a number of 27 digits) contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21000031302299 and 21000031302308.

It is not an unprimeable number, because it can be changed into a prime (21000031302301) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4899678516 + ... + 4899682801.

It is an arithmetic number, because the mean of its divisors is an integer number (5252457666448).

Almost surely, 2^{21000031302331} is an apocalyptic number.

21000031302331 is a deficient number, since it is larger than the sum of its proper divisors (9799363461).

21000031302331 is an equidigital number, since it uses as much as digits as its factorization.

21000031302331 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9799363460.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21000031302331 its reverse (13320313000012), we get a palindrome (34320344302343).

The spelling of 21000031302331 in words is "twenty-one trillion, thirty-one million, three hundred two thousand, three hundred thirty-one".