261635366087 has 2 divisors, whose sum is σ = 261635366088. Its totient is φ = 261635366086.

The previous prime is 261635366053. The next prime is 261635366093. The reversal of 261635366087 is 780663536162.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 261635366087 - 2¹⁰ = 261635365063 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (261635966087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 130817683043 + 130817683044.

It is an arithmetic number, because the mean of its divisors is an integer number (130817683044).

Almost surely, 2^261635366087 is an apocalyptic number.

261635366087 is a deficient number, since it is larger than the sum of its proper divisors (1).

261635366087 is an equidigital number, since it uses as much as digits as its factorization.

261635366087 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 6531840, while the sum is 53.

The spelling of 261635366087 in words is "two hundred sixty-one billion, six hundred thirty-five million, three hundred sixty-six thousand, eighty-seven".