261316533 has 8 divisors (see below), whose sum is σ = 357839008. Its totient is φ = 169502544.

The previous prime is 261316511. The next prime is 261316543. The reversal of 261316533 is 335613162.

It is a happy number.

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

It is not a de Polignac number, because 261316533 - 2⁸ = 261316277 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 261316533.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261316543) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1176991 + ... + 1177212.

It is an arithmetic number, because the mean of its divisors is an integer number (44729876).

Almost surely, 2^261316533 is an apocalyptic number.

It is an amenable number.

261316533 is a deficient number, since it is larger than the sum of its proper divisors (96522475).

261316533 is a wasteful number, since it uses less digits than its factorization.

261316533 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2354243.

The product of its digits is 9720, while the sum is 30.

The square root of 261316533 is about 16165.2879034059. The cubic root of 261316533 is about 639.3258958552.

Adding to 261316533 its reverse (335613162), we get a palindrome (596929695).

The spelling of 261316533 in words is "two hundred sixty-one million, three hundred sixteen thousand, five hundred thirty-three".