856921011 has 16 divisors (see below), whose sum is σ = 1150671744. Its totient is φ = 567240704.

The previous prime is 856921001. The next prime is 856921019. The reversal of 856921011 is 110129658.

It is a cyclic number.

It is not a de Polignac number, because 856921011 - 2⁶ = 856920947 is a prime.

It is not an unprimeable number, because it can be changed into a prime (856921019) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 265936 + ... + 269138.

It is an arithmetic number, because the mean of its divisors is an integer number (71916984).

Almost surely, 2^856921011 is an apocalyptic number.

856921011 is a deficient number, since it is larger than the sum of its proper divisors (293750733).

856921011 is a wasteful number, since it uses less digits than its factorization.

856921011 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3810.

The product of its (nonzero) digits is 4320, while the sum is 33.

The square root of 856921011 is about 29273.2131991006. The cubic root of 856921011 is about 949.8322920945.

The spelling of 856921011 in words is "eight hundred fifty-six million, nine hundred twenty-one thousand, eleven".