856173728560 has 40 divisors (see below), whose sum is σ = 2077151919840. Its totient is φ = 327579512832.

The previous prime is 856173728521. The next prime is 856173728569. The reversal of 856173728560 is 65827371658.

It is a happy number.

It is a tau number, because it is divible by the number of its divisors (40).

It is a super-4 number, since 4×856173728560⁴ (a number of 49 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 856173728495 and 856173728504.

It is not an unprimeable number, because it can be changed into a prime (856173728569) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 232654065 + ... + 232657744.

It is an arithmetic number, because the mean of its divisors is an integer number (51928797996).

Almost surely, 2^856173728560 is an apocalyptic number.

856173728560 is a gapful number since it is divisible by the number (80) formed by its first and last digit.

It is an amenable number.

856173728560 is an abundant number, since it is smaller than the sum of its proper divisors (1220978191280).

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

856173728560 is a wasteful number, since it uses less digits than its factorization.

856173728560 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 465311845 (or 465311839 counting only the distinct ones).

The product of its (nonzero) digits is 16934400, while the sum is 58.

The spelling of 856173728560 in words is "eight hundred fifty-six billion, one hundred seventy-three million, seven hundred twenty-eight thousand, five hundred sixty".