21320310031 has 2 divisors, whose sum is σ = 21320310032. Its totient is φ = 21320310030.

The previous prime is 21320310017. The next prime is 21320310041. The reversal of 21320310031 is 13001302312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21320310031 - 2⁹ = 21320309519 is a prime.

It is a super-2 number, since 2×21320310031² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21320309987 and 21320310014.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21320310041) 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 as a sum of consecutive naturals, namely, 10660155015 + 10660155016.

It is an arithmetic number, because the mean of its divisors is an integer number (10660155016).

Almost surely, 2^21320310031 is an apocalyptic number.

21320310031 is a deficient number, since it is larger than the sum of its proper divisors (1).

21320310031 is an equidigital number, since it uses as much as digits as its factorization.

21320310031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 108, while the sum is 16.

Adding to 21320310031 its reverse (13001302312), we get a palindrome (34321612343).

The spelling of 21320310031 in words is "twenty-one billion, three hundred twenty million, three hundred ten thousand, thirty-one".