21303253031 has 2 divisors, whose sum is σ = 21303253032. Its totient is φ = 21303253030.

The previous prime is 21303253009. The next prime is 21303253079. The reversal of 21303253031 is 13035230312.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21303253031 - 2⁶ = 21303252967 is a prime.

It is a super-2 number, since 2×21303253031² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21303252988 and 21303253006.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21303253091) 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, 10651626515 + 10651626516.

It is an arithmetic number, because the mean of its divisors is an integer number (10651626516).

Almost surely, 2^21303253031 is an apocalyptic number.

21303253031 is a deficient number, since it is larger than the sum of its proper divisors (1).

21303253031 is an equidigital number, since it uses as much as digits as its factorization.

21303253031 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1620, while the sum is 23.

Adding to 21303253031 its reverse (13035230312), we get a palindrome (34338483343).

The spelling of 21303253031 in words is "twenty-one billion, three hundred three million, two hundred fifty-three thousand, thirty-one".