260398921905 has 20 divisors (see below), whose sum is σ = 466789179252. Its totient is φ = 138879424800.

The previous prime is 260398921841. The next prime is 260398921927. The reversal of 260398921905 is 509129893062.

It is a happy number.

260398921905 is a `hidden beast` number, since 2 + 60 + 398 + 9 + 2 + 190 + 5 = 666.

260398921905 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 2 ways, for example, as 74458582641 + 185940339264 = 272871^2 + 431208^2 .

It is not a de Polignac number, because 260398921905 - 2⁶ = 260398921841 is a prime.

It is an unprimeable number.

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 in 19 ways as a sum of consecutive naturals, for example, 321479746 + ... + 321480555.

Almost surely, 2^260398921905 is an apocalyptic number.

It is an amenable number.

260398921905 is a deficient number, since it is larger than the sum of its proper divisors (206390257347).

260398921905 is an equidigital number, since it uses as much as digits as its factorization.

260398921905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 642960318 (or 642960309 counting only the distinct ones).

The product of its (nonzero) digits is 2099520, while the sum is 54.

The spelling of 260398921905 in words is "two hundred sixty billion, three hundred ninety-eight million, nine hundred twenty-one thousand, nine hundred five".