866620397344 has 72 divisors (see below), whose sum is σ = 1951842427668. Its totient is φ = 376450437120.

The previous prime is 866620397341. The next prime is 866620397387. The reversal of 866620397344 is 443793026668.

It is a happy number.

It can be written as a sum of positive squares in 6 ways, for example, as 396381049744 + 470239347600 = 629588^2 + 685740^2 .

It is not an unprimeable number, because it can be changed into a prime (866620397341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 3483967 + ... + 3724414.

Almost surely, 2^866620397344 is an apocalyptic number.

It is an amenable number.

866620397344 is an abundant number, since it is smaller than the sum of its proper divisors (1085222030324).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

866620397344 is a wasteful number, since it uses less digits than its factorization.

866620397344 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7208438 (or 7208413 counting only the distinct ones).

The product of its (nonzero) digits is 31352832, while the sum is 58.

The spelling of 866620397344 in words is "eight hundred sixty-six billion, six hundred twenty million, three hundred ninety-seven thousand, three hundred forty-four".