25654781 has 2 divisors, whose sum is σ = 25654782. Its totient is φ = 25654780.

The previous prime is 25654753. The next prime is 25654823. The reversal of 25654781 is 18745652.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 23609881 + 2044900 = 4859^2 + 1430^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25654781 is a prime.

It is a super-2 number, since 2×25654781² = 1316335576315922, which contains 22 as substring.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25654711) 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, 12827390 + 12827391.

It is an arithmetic number, because the mean of its divisors is an integer number (12827391).

Almost surely, 2^25654781 is an apocalyptic number.

It is an amenable number.

25654781 is a deficient number, since it is larger than the sum of its proper divisors (1).

25654781 is an equidigital number, since it uses as much as digits as its factorization.

25654781 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 67200, while the sum is 38.

The square root of 25654781 is about 5065.0548861784. The cubic root of 25654781 is about 294.9325940027.

The spelling of 25654781 in words is "twenty-five million, six hundred fifty-four thousand, seven hundred eighty-one".