261273485 has 12 divisors (see below), whose sum is σ = 344622684. Its totient is φ = 190016640.

The previous prime is 261273479. The next prime is 261273511. The reversal of 261273485 is 584372162.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 196084009 + 65189476 = 14003^2 + 8074^2 .

It is not a de Polignac number, because 261273485 - 2¹⁰ = 261272461 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 11 ways as a sum of consecutive naturals, for example, 215324 + ... + 216533.

It is an arithmetic number, because the mean of its divisors is an integer number (28718557).

Almost surely, 2^261273485 is an apocalyptic number.

It is an amenable number.

261273485 is a deficient number, since it is larger than the sum of its proper divisors (83349199).

261273485 is a wasteful number, since it uses less digits than its factorization.

261273485 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 431884 (or 431873 counting only the distinct ones).

The product of its digits is 80640, while the sum is 38.

The square root of 261273485 is about 16163.9563535664. The cubic root of 261273485 is about 639.2907874597.

The spelling of 261273485 in words is "two hundred sixty-one million, two hundred seventy-three thousand, four hundred eighty-five".