261236215 has 8 divisors (see below), whose sum is σ = 321129648. Its totient is φ = 203891520.

The previous prime is 261236203. The next prime is 261236219. The reversal of 261236215 is 512632162.

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

It is not a de Polignac number, because 261236215 - 2⁹ = 261235703 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261236219) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 636957 + ... + 637366.

It is an arithmetic number, because the mean of its divisors is an integer number (40141206).

Almost surely, 2^261236215 is an apocalyptic number.

261236215 is a deficient number, since it is larger than the sum of its proper divisors (59893433).

261236215 is a wasteful number, since it uses less digits than its factorization.

261236215 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1274369.

The product of its digits is 4320, while the sum is 28.

The square root of 261236215 is about 16162.8034387602. The cubic root of 261236215 is about 639.2603882777.

Adding to 261236215 its reverse (512632162), we get a palindrome (773868377).

The spelling of 261236215 in words is "two hundred sixty-one million, two hundred thirty-six thousand, two hundred fifteen".