261236321 has 8 divisors (see below), whose sum is σ = 271382400. Its totient is φ = 251166160.

The previous prime is 261236303. The next prime is 261236341. The reversal of 261236321 is 123632162.

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 261236321 - 2²⁶ = 194127457 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261236341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11915 + ... + 25776.

It is an arithmetic number, because the mean of its divisors is an integer number (33922800).

Almost surely, 2^261236321 is an apocalyptic number.

It is an amenable number.

261236321 is a deficient number, since it is larger than the sum of its proper divisors (10146079).

261236321 is a wasteful number, since it uses less digits than its factorization.

261236321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37959.

The product of its digits is 2592, while the sum is 26.

The square root of 261236321 is about 16162.8067178940. The cubic root of 261236321 is about 639.2604747404.

Adding to 261236321 its reverse (123632162), we get a palindrome (384868483).

The spelling of 261236321 in words is "two hundred sixty-one million, two hundred thirty-six thousand, three hundred twenty-one".