25805531 has 2 divisors, whose sum is σ = 25805532. Its totient is φ = 25805530.

The previous prime is 25805513. The next prime is 25805537. The reversal of 25805531 is 13550852.

Together with previous prime (25805513) it forms an Ormiston pair, because they use the same digits, order apart.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 25805531 - 2⁶ = 25805467 is a prime.

It is a super-2 number, since 2×25805531² = 1331850860383922, which contains 22 as substring.

It is a Chen prime.

It is a junction number, because it is equal to n+sod(n) for n = 25805494 and 25805503.

It is not a weakly prime, because it can be changed into another prime (25805537) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12902765 + 12902766.

It is an arithmetic number, because the mean of its divisors is an integer number (12902766).

Almost surely, 2^25805531 is an apocalyptic number.

25805531 is a deficient number, since it is larger than the sum of its proper divisors (1).

25805531 is an equidigital number, since it uses as much as digits as its factorization.

25805531 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 6000, while the sum is 29.

The square root of 25805531 is about 5079.9144677839. The cubic root of 25805531 is about 295.5091504196.

The spelling of 25805531 in words is "twenty-five million, eight hundred five thousand, five hundred thirty-one".