25305103981 has 2 divisors, whose sum is σ = 25305103982. Its totient is φ = 25305103980.

The previous prime is 25305103961. The next prime is 25305104009. The reversal of 25305103981 is 18930150352.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 24952941225 + 352162756 = 157965^2 + 18766^2 .

It is a cyclic number.

It is not a de Polignac number, because 25305103981 - 2⁷ = 25305103853 is a prime.

It is a super-2 number, since 2×25305103981² (a number of 22 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 25305103981.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (25305103931) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 12652551990 + 12652551991.

It is an arithmetic number, because the mean of its divisors is an integer number (12652551991).

Almost surely, 2^25305103981 is an apocalyptic number.

It is an amenable number.

25305103981 is a deficient number, since it is larger than the sum of its proper divisors (1).

25305103981 is an equidigital number, since it uses as much as digits as its factorization.

25305103981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 32400, while the sum is 37.

It can be divided in two parts, 25305 and 103981, that added together give a triangular number (129286 = T₅₀₈).

The spelling of 25305103981 in words is "twenty-five billion, three hundred five million, one hundred three thousand, nine hundred eighty-one".