261576487 has 2 divisors, whose sum is σ = 261576488. Its totient is φ = 261576486.

The previous prime is 261576473. The next prime is 261576499. The reversal of 261576487 is 784675162.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-261576487 is a prime.

It is a super-3 number, since 3×261576487³ (a number of 26 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261576457) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130788243 + 130788244.

It is an arithmetic number, because the mean of its divisors is an integer number (130788244).

Almost surely, 2^261576487 is an apocalyptic number.

261576487 is a deficient number, since it is larger than the sum of its proper divisors (1).

261576487 is an equidigital number, since it uses as much as digits as its factorization.

261576487 is an evil number, because the sum of its binary digits is even.

The product of its digits is 564480, while the sum is 46.

The square root of 261576487 is about 16173.3264049174. The cubic root of 261576487 is about 639.5378230569.

The spelling of 261576487 in words is "two hundred sixty-one million, five hundred seventy-six thousand, four hundred eighty-seven".