21425555231 has 2 divisors, whose sum is σ = 21425555232. Its totient is φ = 21425555230.

The previous prime is 21425555167. The next prime is 21425555297. The reversal of 21425555231 is 13255552412.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21425555231 - 2⁶ = 21425555167 is a prime.

It is a super-2 number, since 2×21425555231² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21425555191 and 21425555200.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21425555831) 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, 10712777615 + 10712777616.

It is an arithmetic number, because the mean of its divisors is an integer number (10712777616).

Almost surely, 2^21425555231 is an apocalyptic number.

21425555231 is a deficient number, since it is larger than the sum of its proper divisors (1).

21425555231 is an equidigital number, since it uses as much as digits as its factorization.

21425555231 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 60000, while the sum is 35.

The spelling of 21425555231 in words is "twenty-one billion, four hundred twenty-five million, five hundred fifty-five thousand, two hundred thirty-one".