261646253701201 has 8 divisors (see below), whose sum is σ = 263962056816360. Its totient is φ = 259330456718592.

The previous prime is 261646253701193. The next prime is 261646253701243. The reversal of 261646253701201 is 102107352646162.

It can be written as a sum of positive squares in 4 ways, for example, as 88254770148801 + 173391483552400 = 9394401^2 + 13167820^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 261646253701201 - 2³ = 261646253701193 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261646253701291) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 151272991 + ... + 152992843.

It is an arithmetic number, because the mean of its divisors is an integer number (32995257102045).

Almost surely, 2^{261646253701201} is an apocalyptic number.

It is an amenable number.

261646253701201 is a deficient number, since it is larger than the sum of its proper divisors (2315803115159).

261646253701201 is a wasteful number, since it uses less digits than its factorization.

261646253701201 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3066275.

The product of its (nonzero) digits is 725760, while the sum is 46.

The spelling of 261646253701201 in words is "two hundred sixty-one trillion, six hundred forty-six billion, two hundred fifty-three million, seven hundred one thousand, two hundred one".