25435561 has 2 divisors, whose sum is σ = 25435562. Its totient is φ = 25435560.

The previous prime is 25435517. The next prime is 25435573. The reversal of 25435561 is 16553452.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17347225 + 8088336 = 4165^2 + 2844^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-25435561 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (25435591) 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, 12717780 + 12717781.

It is an arithmetic number, because the mean of its divisors is an integer number (12717781).

Almost surely, 2^25435561 is an apocalyptic number.

It is an amenable number.

25435561 is a deficient number, since it is larger than the sum of its proper divisors (1).

25435561 is an equidigital number, since it uses as much as digits as its factorization.

25435561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 18000, while the sum is 31.

The square root of 25435561 is about 5043.3680214714. The cubic root of 25435561 is about 294.0901238504.

The spelling of 25435561 in words is "twenty-five million, four hundred thirty-five thousand, five hundred sixty-one".