259885981 has 2 divisors, whose sum is σ = 259885982. Its totient is φ = 259885980.

The previous prime is 259885961. The next prime is 259885999. The reversal of 259885981 is 189588952.

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., 233784100 + 26101881 = 15290^2 + 5109^2 .

It is a cyclic number.

It is not a de Polignac number, because 259885981 - 2⁹ = 259885469 is a prime.

It is a super-2 number, since 2×259885981² = 135081446240664722, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (259885931) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 129942990 + 129942991.

It is an arithmetic number, because the mean of its divisors is an integer number (129942991).

Almost surely, 2^259885981 is an apocalyptic number.

It is an amenable number.

259885981 is a deficient number, since it is larger than the sum of its proper divisors (1).

259885981 is an equidigital number, since it uses as much as digits as its factorization.

259885981 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2073600, while the sum is 55.

The square root of 259885981 is about 16120.9795297928. The cubic root of 259885981 is about 638.1571179422.

The spelling of 259885981 in words is "two hundred fifty-nine million, eight hundred eighty-five thousand, nine hundred eighty-one".