25884943661 has 2 divisors, whose sum is σ = 25884943662. Its totient is φ = 25884943660.

The previous prime is 25884943603. The next prime is 25884943691. The reversal of 25884943661 is 16634948852.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 17707358761 + 8177584900 = 133069^2 + 90430^2 .

It is a cyclic number.

It is not a de Polignac number, because 25884943661 - 2²⁶ = 25817834797 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 25884943597 and 25884943606.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25884943691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12942471830 + 12942471831.

It is an arithmetic number, because the mean of its divisors is an integer number (12942471831).

Almost surely, 2^25884943661 is an apocalyptic number.

It is an amenable number.

25884943661 is a deficient number, since it is larger than the sum of its proper divisors (1).

25884943661 is an equidigital number, since it uses as much as digits as its factorization.

25884943661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 9953280, while the sum is 56.

The spelling of 25884943661 in words is "twenty-five billion, eight hundred eighty-four million, nine hundred forty-three thousand, six hundred sixty-one".