856903064081 has 4 divisors (see below), whose sum is σ = 907309126692. Its totient is φ = 806497001472.

The previous prime is 856903064071. The next prime is 856903064099. The reversal of 856903064081 is 180460309658.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 180460309658 = 2 ⋅90230154829.

It can be written as a sum of positive squares in 2 ways, for example, as 339791063056 + 517112001025 = 582916^2 + 719105^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-856903064081 is a prime.

It is a super-2 number, since 2×856903064081² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (856903064041) 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, 25203031280 + ... + 25203031313.

It is an arithmetic number, because the mean of its divisors is an integer number (226827281673).

Almost surely, 2^856903064081 is an apocalyptic number.

It is an amenable number.

856903064081 is a deficient number, since it is larger than the sum of its proper divisors (50406062611).

856903064081 is a wasteful number, since it uses less digits than its factorization.

856903064081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 50406062610.

The product of its (nonzero) digits is 1244160, while the sum is 50.

The spelling of 856903064081 in words is "eight hundred fifty-six billion, nine hundred three million, sixty-four thousand, eighty-one".