260121002665 has 4 divisors (see below), whose sum is σ = 312145203204. Its totient is φ = 208096802128.

The previous prime is 260121002567. The next prime is 260121002671. The reversal of 260121002665 is 566200121062.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 26240436121 + 233880566544 = 161989^2 + 483612^2 .

It is a cyclic number.

It is not a de Polignac number, because 260121002665 - 2⁹ = 260121002153 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26012100262 + ... + 26012100271.

It is an arithmetic number, because the mean of its divisors is an integer number (78036300801).

Almost surely, 2^260121002665 is an apocalyptic number.

It is an amenable number.

260121002665 is a deficient number, since it is larger than the sum of its proper divisors (52024200539).

260121002665 is an equidigital number, since it uses as much as digits as its factorization.

260121002665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 52024200538.

The product of its (nonzero) digits is 8640, while the sum is 31.

The spelling of 260121002665 in words is "two hundred sixty billion, one hundred twenty-one million, two thousand, six hundred sixty-five".