261670201 has 4 divisors (see below), whose sum is σ = 281798692. Its totient is φ = 241541712.

The previous prime is 261670183. The next prime is 261670237. The reversal of 261670201 is 102076162.

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 39690000 + 221980201 = 6300^2 + 14899^2 .

It is a cyclic number.

It is not a de Polignac number, because 261670201 - 2¹⁵ = 261637433 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261670601) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10064226 + ... + 10064251.

It is an arithmetic number, because the mean of its divisors is an integer number (70449673).

Almost surely, 2^261670201 is an apocalyptic number.

It is an amenable number.

261670201 is a deficient number, since it is larger than the sum of its proper divisors (20128491).

261670201 is a wasteful number, since it uses less digits than its factorization.

261670201 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20128490.

The product of its (nonzero) digits is 1008, while the sum is 25.

The square root of 261670201 is about 16176.2233231370. The cubic root of 261670201 is about 639.6141888550.

The spelling of 261670201 in words is "two hundred sixty-one million, six hundred seventy thousand, two hundred one".