856220377 has 2 divisors, whose sum is σ = 856220378. Its totient is φ = 856220376.

The previous prime is 856220363. The next prime is 856220383. The reversal of 856220377 is 773022658.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 526289481 + 329930896 = 22941^2 + 18164^2 .

It is a cyclic number.

It is not a de Polignac number, because 856220377 - 2¹⁹ = 855696089 is a prime.

It is a super-2 number, since 2×856220377² = 1466226667980044258, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (856229377) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 428110188 + 428110189.

It is an arithmetic number, because the mean of its divisors is an integer number (428110189).

Almost surely, 2^856220377 is an apocalyptic number.

It is an amenable number.

856220377 is a deficient number, since it is larger than the sum of its proper divisors (1).

856220377 is an equidigital number, since it uses as much as digits as its factorization.

856220377 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 141120, while the sum is 40.

The square root of 856220377 is about 29261.2435996832. The cubic root of 856220377 is about 949.5733548674.

The spelling of 856220377 in words is "eight hundred fifty-six million, two hundred twenty thousand, three hundred seventy-seven".