21425121331 has 2 divisors, whose sum is σ = 21425121332. Its totient is φ = 21425121330.

The previous prime is 21425121313. The next prime is 21425121379. The reversal of 21425121331 is 13312152412.

Together with previous prime (21425121313) it forms an Ormiston pair, because they use the same digits, order apart.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21425121331 is a prime.

It is a super-2 number, since 2×21425121331² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21425121296 and 21425121305.

It is not a weakly prime, because it can be changed into another prime (21425121931) 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, 10712560665 + 10712560666.

It is an arithmetic number, because the mean of its divisors is an integer number (10712560666).

Almost surely, 2^21425121331 is an apocalyptic number.

21425121331 is a deficient number, since it is larger than the sum of its proper divisors (1).

21425121331 is an equidigital number, since it uses as much as digits as its factorization.

21425121331 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1440, while the sum is 25.

Adding to 21425121331 its reverse (13312152412), we get a palindrome (34737273743).

The spelling of 21425121331 in words is "twenty-one billion, four hundred twenty-five million, one hundred twenty-one thousand, three hundred thirty-one".