261323461 has 16 divisors (see below), whose sum is σ = 304374528. Its totient is φ = 219744000.

The previous prime is 261323453. The next prime is 261323471. The reversal of 261323461 is 164323162.

It is not a de Polignac number, because 261323461 - 2³ = 261323453 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 (261323441) 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 15 ways as a sum of consecutive naturals, for example, 78256 + ... + 81526.

It is an arithmetic number, because the mean of its divisors is an integer number (19023408).

Almost surely, 2^261323461 is an apocalyptic number.

It is an amenable number.

261323461 is a deficient number, since it is larger than the sum of its proper divisors (43051067).

261323461 is a wasteful number, since it uses less digits than its factorization.

261323461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3492.

The product of its digits is 5184, while the sum is 28.

The square root of 261323461 is about 16165.5021883021. The cubic root of 261323461 is about 639.3315457218.

The spelling of 261323461 in words is "two hundred sixty-one million, three hundred twenty-three thousand, four hundred sixty-one".