866788526243441 has 4 divisors (see below), whose sum is σ = 866961572470500. Its totient is φ = 866615480016384.

The previous prime is 866788526243429. The next prime is 866788526243443. The reversal of 866788526243441 is 144342625887668.

It is a happy number.

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 208337324871025 + 658451201372416 = 14433895^2 + 25660304^2 .

It is a cyclic number.

It is not a de Polignac number, because 866788526243441 - 2⁶ = 866788526243377 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (866788526243443) 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, 86523106016 + ... + 86523116033.

It is an arithmetic number, because the mean of its divisors is an integer number (216740393117625).

Almost surely, 2^{866788526243441} is an apocalyptic number.

It is an amenable number.

866788526243441 is a deficient number, since it is larger than the sum of its proper divisors (173046227059).

866788526243441 is a wasteful number, since it uses less digits than its factorization.

866788526243441 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 173046227058.

The product of its digits is 2972712960, while the sum is 74.

The spelling of 866788526243441 in words is "eight hundred sixty-six trillion, seven hundred eighty-eight billion, five hundred twenty-six million, two hundred forty-three thousand, four hundred forty-one".