25561218703 has 2 divisors, whose sum is σ = 25561218704. Its totient is φ = 25561218702.

The previous prime is 25561218701. The next prime is 25561218763. The reversal of 25561218703 is 30781216552.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 25561218703 - 2¹ = 25561218701 is a prime.

Together with 25561218701, it forms a pair of twin primes.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25561218701) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12780609351 + 12780609352.

It is an arithmetic number, because the mean of its divisors is an integer number (12780609352).

Almost surely, 2^25561218703 is an apocalyptic number.

25561218703 is a deficient number, since it is larger than the sum of its proper divisors (1).

25561218703 is an equidigital number, since it uses as much as digits as its factorization.

25561218703 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 100800, while the sum is 40.

The spelling of 25561218703 in words is "twenty-five billion, five hundred sixty-one million, two hundred eighteen thousand, seven hundred three".