21020332331 has 2 divisors, whose sum is σ = 21020332332. Its totient is φ = 21020332330.

The previous prime is 21020332309. The next prime is 21020332337. The reversal of 21020332331 is 13323302012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21020332331 - 2¹⁰ = 21020331307 is a prime.

It is a super-2 number, since 2×21020332331² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21020332337) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10510166165 + 10510166166.

It is an arithmetic number, because the mean of its divisors is an integer number (10510166166).

Almost surely, 2^21020332331 is an apocalyptic number.

21020332331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21020332331 is an equidigital number, since it uses as much as digits as its factorization.

21020332331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 648, while the sum is 20.

Adding to 21020332331 its reverse (13323302012), we get a palindrome (34343634343).

The spelling of 21020332331 in words is "twenty-one billion, twenty million, three hundred thirty-two thousand, three hundred thirty-one".