850509021681 has 12 divisors (see below), whose sum is σ = 1340196034320. Its totient is φ = 515460013080.

The previous prime is 850509021679. The next prime is 850509021689. The reversal of 850509021681 is 186120905058.

It is a happy number.

850509021681 is a `hidden beast` number, since 8 + 50 + 509 + 0 + 2 + 16 + 81 = 666.

It is not a de Polignac number, because 850509021681 - 2¹ = 850509021679 is a prime.

It is a super-2 number, since 2×850509021681² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (850509021689) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 4295500011 + ... + 4295500208.

It is an arithmetic number, because the mean of its divisors is an integer number (111683002860).

Almost surely, 2^850509021681 is an apocalyptic number.

It is an amenable number.

850509021681 is a deficient number, since it is larger than the sum of its proper divisors (489687012639).

850509021681 is a wasteful number, since it uses less digits than its factorization.

850509021681 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8591000236 (or 8591000233 counting only the distinct ones).

The product of its (nonzero) digits is 172800, while the sum is 45.

The spelling of 850509021681 in words is "eight hundred fifty billion, five hundred nine million, twenty-one thousand, six hundred eighty-one".