856220381 has 8 divisors (see below), whose sum is σ = 864043224. Its totient is φ = 848427840.

The previous prime is 856220377. The next prime is 856220383. The reversal of 856220381 is 183022658.

856220381 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 5331481 + 850888900 = 2309^2 + 29170^2 .

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

It is a cyclic number.

It is not a de Polignac number, because 856220381 - 2² = 856220377 is a prime.

It is a super-2 number, since 2×856220381² = 1466226681679570322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (856220383) 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, 51251 + ... + 65871.

It is an arithmetic number, because the mean of its divisors is an integer number (108005403).

Almost surely, 2^856220381 is an apocalyptic number.

It is an amenable number.

856220381 is a deficient number, since it is larger than the sum of its proper divisors (7822843).

856220381 is a wasteful number, since it uses less digits than its factorization.

856220381 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15151.

The product of its (nonzero) digits is 23040, while the sum is 35.

The square root of 856220381 is about 29261.2436680330. The cubic root of 856220381 is about 949.5733563461.

The spelling of 856220381 in words is "eight hundred fifty-six million, two hundred twenty thousand, three hundred eighty-one".