866763551212505 has 4 divisors (see below), whose sum is σ = 1040116261455012. Its totient is φ = 693410840970000.

The previous prime is 866763551212501. The next prime is 866763551212543. The reversal of 866763551212505 is 505212155367668.

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

It can be written as a sum of positive squares in 2 ways, for example, as 587734055373529 + 279029495838976 = 24243227^2 + 16704176^2 .

It is not a de Polignac number, because 866763551212505 - 2² = 866763551212501 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (866763551212501) 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, 86676355121246 + ... + 86676355121255.

It is an arithmetic number, because the mean of its divisors is an integer number (260029065363753).

Almost surely, 2^{866763551212505} is an apocalyptic number.

It is an amenable number.

866763551212505 is a deficient number, since it is larger than the sum of its proper divisors (173352710242507).

866763551212505 is a wasteful number, since it uses less digits than its factorization.

866763551212505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173352710242506.

The product of its (nonzero) digits is 90720000, while the sum is 62.

The spelling of 866763551212505 in words is "eight hundred sixty-six trillion, seven hundred sixty-three billion, five hundred fifty-one million, two hundred twelve thousand, five hundred five".