261511479 has 12 divisors (see below), whose sum is σ = 380002896. Its totient is φ = 173296032.

The previous prime is 261511469. The next prime is 261511483. The reversal of 261511479 is 974115162.

It is not a de Polignac number, because 261511479 - 2⁴ = 261511463 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261511469) 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 11 ways as a sum of consecutive naturals, for example, 85494 + ... + 88499.

It is an arithmetic number, because the mean of its divisors is an integer number (31666908).

Almost surely, 2^261511479 is an apocalyptic number.

261511479 is a deficient number, since it is larger than the sum of its proper divisors (118491417).

261511479 is a wasteful number, since it uses less digits than its factorization.

261511479 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 174166 (or 174163 counting only the distinct ones).

The product of its digits is 15120, while the sum is 36.

The square root of 261511479 is about 16171.3165512274. The cubic root of 261511479 is about 639.4848385297.

The spelling of 261511479 in words is "two hundred sixty-one million, five hundred eleven thousand, four hundred seventy-nine".