856221278 has 16 divisors (see below), whose sum is σ = 1430901504. Its totient is φ = 380910360.

The previous prime is 856221241. The next prime is 856221313. The reversal of 856221278 is 872122658.

856221278 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a super-2 number, since 2×856221278² = 1466229753799906568, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 413000 + ... + 415067.

It is an arithmetic number, because the mean of its divisors is an integer number (89431344).

Almost surely, 2^856221278 is an apocalyptic number.

856221278 is a deficient number, since it is larger than the sum of its proper divisors (574680226).

856221278 is a wasteful number, since it uses less digits than its factorization.

856221278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 828127.

The product of its digits is 107520, while the sum is 41.

The square root of 856221278 is about 29261.2589954704. The cubic root of 856221278 is about 949.5736879457.

The spelling of 856221278 in words is "eight hundred fifty-six million, two hundred twenty-one thousand, two hundred seventy-eight".