261236287383511 has 16 divisors (see below), whose sum is σ = 297376684830720. Its totient is φ = 227161232701920.

The previous prime is 261236287383509. The next prime is 261236287383529. The reversal of 261236287383511 is 115383782632162.

It is not a de Polignac number, because 261236287383511 - 2¹ = 261236287383509 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261236287383551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 82572106 + ... + 85677448.

It is an arithmetic number, because the mean of its divisors is an integer number (18586042801920).

Almost surely, 2^{261236287383511} is an apocalyptic number.

261236287383511 is a deficient number, since it is larger than the sum of its proper divisors (36140397447209).

261236287383511 is a wasteful number, since it uses less digits than its factorization.

261236287383511 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3437886.

The product of its digits is 17418240, while the sum is 58.

The spelling of 261236287383511 in words is "two hundred sixty-one trillion, two hundred thirty-six billion, two hundred eighty-seven million, three hundred eighty-three thousand, five hundred eleven".