25661350505 has 16 divisors (see below), whose sum is σ = 37044958080. Its totient is φ = 16670230272.

The previous prime is 25661350489. The next prime is 25661350511. The reversal of 25661350505 is 50505316652.

It is a cyclic number.

It is not a de Polignac number, because 25661350505 - 2⁴ = 25661350489 is a prime.

It is an unprimeable number.

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 in 15 ways as a sum of consecutive naturals, for example, 19293584 + ... + 19294913.

It is an arithmetic number, because the mean of its divisors is an integer number (2315309880).

Almost surely, 2^25661350505 is an apocalyptic number.

It is an amenable number.

25661350505 is a deficient number, since it is larger than the sum of its proper divisors (11383607575).

25661350505 is a wasteful number, since it uses less digits than its factorization.

25661350505 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 38588528.

The product of its (nonzero) digits is 135000, while the sum is 38.

The spelling of 25661350505 in words is "twenty-five billion, six hundred sixty-one million, three hundred fifty thousand, five hundred five".