261242523 has 8 divisors (see below), whose sum is σ = 387026000. Its totient is φ = 174161664.

The previous prime is 261242521. The next prime is 261242537. The reversal of 261242523 is 325242162.

It is a happy number.

261242523 is a `hidden beast` number, since 2 + 612 + 4 + 25 + 23 = 666.

It is not a de Polignac number, because 261242523 - 2¹ = 261242521 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (27), and also a Moran number because the ratio is a prime number: 9675649 = 261242523 / (2 + 6 + 1 + 2 + 4 + 2 + 5 + 2 + 3).

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (261242521) 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, 4837798 + ... + 4837851.

It is an arithmetic number, because the mean of its divisors is an integer number (48378250).

Almost surely, 2^261242523 is an apocalyptic number.

261242523 is a deficient number, since it is larger than the sum of its proper divisors (125783477).

261242523 is an equidigital number, since it uses as much as digits as its factorization.

261242523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9675658 (or 9675652 counting only the distinct ones).

The product of its digits is 5760, while the sum is 27.

The square root of 261242523 is about 16162.9985769968. The cubic root of 261242523 is about 639.2655335853.

Adding to 261242523 its reverse (325242162), we get a palindrome (586484685).

The spelling of 261242523 in words is "two hundred sixty-one million, two hundred forty-two thousand, five hundred twenty-three".