25646669077 has 2 divisors, whose sum is σ = 25646669078. Its totient is φ = 25646669076.

The previous prime is 25646669063. The next prime is 25646669089. The reversal of 25646669077 is 77096664652.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 23004092241 + 2642576836 = 151671^2 + 51406^2 .

It is a cyclic number.

It is not a de Polignac number, because 25646669077 - 2¹⁹ = 25646144789 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25646669057) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12823334538 + 12823334539.

It is an arithmetic number, because the mean of its divisors is an integer number (12823334539).

Almost surely, 2^25646669077 is an apocalyptic number.

It is an amenable number.

25646669077 is a deficient number, since it is larger than the sum of its proper divisors (1).

25646669077 is an equidigital number, since it uses as much as digits as its factorization.

25646669077 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 22861440, while the sum is 58.

The spelling of 25646669077 in words is "twenty-five billion, six hundred forty-six million, six hundred sixty-nine thousand, seventy-seven".