809757920161 has 16 divisors (see below), whose sum is σ = 891508792320. Its totient is φ = 732156848640.

The previous prime is 809757920143. The next prime is 809757920173. The reversal of 809757920161 is 161029757908.

It is a happy number.

It is not a de Polignac number, because 809757920161 - 2¹⁷ = 809757789089 is a prime.

It is a super-3 number, since 3×809757920161³ (a number of 37 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (809757920131) 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 15 ways as a sum of consecutive naturals, for example, 5535621 + ... + 5680018.

It is an arithmetic number, because the mean of its divisors is an integer number (55719299520).

Almost surely, 2^809757920161 is an apocalyptic number.

It is an amenable number.

809757920161 is a deficient number, since it is larger than the sum of its proper divisors (81750872159).

809757920161 is a wasteful number, since it uses less digits than its factorization.

809757920161 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11215824.

The product of its (nonzero) digits is 1905120, while the sum is 55.

The spelling of 809757920161 in words is "eight hundred nine billion, seven hundred fifty-seven million, nine hundred twenty thousand, one hundred sixty-one".