918585221977 has 4 divisors (see below), whose sum is σ = 943411849636. Its totient is φ = 893758594320.

The previous prime is 918585221929. The next prime is 918585222001. The reversal of 918585221977 is 779122585819.

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 705551280841 + 213033941136 = 839971^2 + 461556^2 .

It is a cyclic number.

It is not a de Polignac number, because 918585221977 - 2²⁷ = 918451004249 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (918585221927) 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, 12413313774 + ... + 12413313847.

It is an arithmetic number, because the mean of its divisors is an integer number (235852962409).

Almost surely, 2^918585221977 is an apocalyptic number.

It is an amenable number.

918585221977 is a deficient number, since it is larger than the sum of its proper divisors (24826627659).

918585221977 is a wasteful number, since it uses less digits than its factorization.

918585221977 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 24826627658.

The product of its digits is 25401600, while the sum is 64.

The spelling of 918585221977 in words is "nine hundred eighteen billion, five hundred eighty-five million, two hundred twenty-one thousand, nine hundred seventy-seven".