856829701978 has 8 divisors (see below), whose sum is σ = 1285602271668. Its totient is φ = 428295611424.

The previous prime is 856829701967. The next prime is 856829701979. The reversal of 856829701978 is 879107928658.

It can be written as a sum of positive squares in 2 ways, for example, as 831629091969 + 25200610009 = 911937^2 + 158747^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×856829701978² (a number of 25 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (856829701979) 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, 59610801 + ... + 59625172.

Almost surely, 2^856829701978 is an apocalyptic number.

856829701978 is a deficient number, since it is larger than the sum of its proper divisors (428772569690).

856829701978 is a wasteful number, since it uses less digits than its factorization.

856829701978 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 119239568.

The product of its (nonzero) digits is 121927680, while the sum is 70.

The spelling of 856829701978 in words is "eight hundred fifty-six billion, eight hundred twenty-nine million, seven hundred one thousand, nine hundred seventy-eight".