25784647462661 has 2 divisors, whose sum is σ = 25784647462662. Its totient is φ = 25784647462660.

The previous prime is 25784647462633. The next prime is 25784647462747. The reversal of 25784647462661 is 16626474648752.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 18176323756900 + 7608323705761 = 4263370^2 + 2758319^2 .

It is a cyclic number.

It is not a de Polignac number, because 25784647462661 - 2¹⁰ = 25784647461637 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25784647462591 and 25784647462600.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25784647462601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12892323731330 + 12892323731331.

It is an arithmetic number, because the mean of its divisors is an integer number (12892323731331).

Almost surely, 2^{25784647462661} is an apocalyptic number.

It is an amenable number.

25784647462661 is a deficient number, since it is larger than the sum of its proper divisors (1).

25784647462661 is an equidigital number, since it uses as much as digits as its factorization.

25784647462661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 650280960, while the sum is 68.

The spelling of 25784647462661 in words is "twenty-five trillion, seven hundred eighty-four billion, six hundred forty-seven million, four hundred sixty-two thousand, six hundred sixty-one".