866786255656131 has 4 divisors (see below), whose sum is σ = 1155715007541512. Its totient is φ = 577857503770752.

The previous prime is 866786255656103. The next prime is 866786255656141. The reversal of 866786255656131 is 131656552687668.

866786255656131 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 866786255656131 - 2⁶ = 866786255656067 is a prime.

It is a super-2 number, since 2×866786255656131² (a number of 31 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866786255656141) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 144464375942686 + ... + 144464375942691.

It is an arithmetic number, because the mean of its divisors is an integer number (288928751885378).

Almost surely, 2^{866786255656131} is an apocalyptic number.

866786255656131 is a deficient number, since it is larger than the sum of its proper divisors (288928751885381).

866786255656131 is a wasteful number, since it uses less digits than its factorization.

866786255656131 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 288928751885380.

The product of its digits is 2612736000, while the sum is 75.

The spelling of 866786255656131 in words is "eight hundred sixty-six trillion, seven hundred eighty-six billion, two hundred fifty-five million, six hundred fifty-six thousand, one hundred thirty-one".