21340240331 has 2 divisors, whose sum is σ = 21340240332. Its totient is φ = 21340240330.

The previous prime is 21340240277. The next prime is 21340240367. The reversal of 21340240331 is 13304204312.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21340240331 - 2¹⁰ = 21340239307 is a prime.

It is a super-2 number, since 2×21340240331² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21340240297 and 21340240306.

It is not a weakly prime, because it can be changed into another prime (21340240391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10670120165 + 10670120166.

It is an arithmetic number, because the mean of its divisors is an integer number (10670120166).

Almost surely, 2^21340240331 is an apocalyptic number.

21340240331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21340240331 is an equidigital number, since it uses as much as digits as its factorization.

21340240331 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1728, while the sum is 23.

Adding to 21340240331 its reverse (13304204312), we get a palindrome (34644444643).

The spelling of 21340240331 in words is "twenty-one billion, three hundred forty million, two hundred forty thousand, three hundred thirty-one".