856992977 has 2 divisors, whose sum is σ = 856992978. Its totient is φ = 856992976.

The previous prime is 856992973. The next prime is 856993013. The reversal of 856992977 is 779299658.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 819734161 + 37258816 = 28631^2 + 6104^2 .

It is a cyclic number.

It is not a de Polignac number, because 856992977 - 2² = 856992973 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (856992973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428496488 + 428496489.

It is an arithmetic number, because the mean of its divisors is an integer number (428496489).

Almost surely, 2^856992977 is an apocalyptic number.

It is an amenable number.

856992977 is a deficient number, since it is larger than the sum of its proper divisors (1).

856992977 is an equidigital number, since it uses as much as digits as its factorization.

856992977 is an evil number, because the sum of its binary digits is even.

The product of its digits is 17146080, while the sum is 62.

The square root of 856992977 is about 29274.4423858081. The cubic root of 856992977 is about 949.8588809774.

The spelling of 856992977 in words is "eight hundred fifty-six million, nine hundred ninety-two thousand, nine hundred seventy-seven".