25467781 has 2 divisors, whose sum is σ = 25467782. Its totient is φ = 25467780.

The previous prime is 25467779. The next prime is 25467787. The reversal of 25467781 is 18776452.

25467781 = T₄₁₁₉ + T₄₁₂₀ + T₄₁₂₁.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 25250625 + 217156 = 5025^2 + 466^2 .

It is a cyclic number.

It is not a de Polignac number, because 25467781 - 2¹ = 25467779 is a prime.

It is a super-2 number, since 2×25467781² = 1297215738127922, which contains 22 as substring.

Together with 25467779, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25467787) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12733890 + 12733891.

It is an arithmetic number, because the mean of its divisors is an integer number (12733891).

Almost surely, 2^25467781 is an apocalyptic number.

25467781 is the 4121-st centered triangular number.

It is an amenable number.

25467781 is a deficient number, since it is larger than the sum of its proper divisors (1).

25467781 is an equidigital number, since it uses as much as digits as its factorization.

25467781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 94080, while the sum is 40.

The square root of 25467781 is about 5046.5613044924. The cubic root of 25467781 is about 294.2142490938.

The spelling of 25467781 in words is "twenty-five million, four hundred sixty-seven thousand, seven hundred eighty-one".