866805731853555 has 64 divisors (see below), whose sum is σ = 1498898140508160. Its totient is φ = 425215597095936.

The previous prime is 866805731853553. The next prime is 866805731853569. The reversal of 866805731853555 is 555358137508668.

It is not a de Polignac number, because 866805731853555 - 2¹ = 866805731853553 is a prime.

It is a super-2 number, since 2×866805731853555² (a number of 31 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (866805731853553) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 80300706 + ... + 90453384.

It is an arithmetic number, because the mean of its divisors is an integer number (23420283445440).

Almost surely, 2^{866805731853555} is an apocalyptic number.

866805731853555 is a deficient number, since it is larger than the sum of its proper divisors (632092408654605).

866805731853555 is a wasteful number, since it uses less digits than its factorization.

866805731853555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10154260.

The product of its (nonzero) digits is 3628800000, while the sum is 75.

The spelling of 866805731853555 in words is "eight hundred sixty-six trillion, eight hundred five billion, seven hundred thirty-one million, eight hundred fifty-three thousand, five hundred fifty-five".