6856504381 has 2 divisors, whose sum is σ = 6856504382. Its totient is φ = 6856504380.

The previous prime is 6856504367. The next prime is 6856504387. The reversal of 6856504381 is 1834056586.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 5233220281 + 1623284100 = 72341^2 + 40290^2 .

It is a cyclic number.

It is not a de Polignac number, because 6856504381 - 2²⁷ = 6722286653 is a prime.

It is a super-2 number, since 2×6856504381² = 94023304653344386322, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6856504387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3428252190 + 3428252191.

It is an arithmetic number, because the mean of its divisors is an integer number (3428252191).

Almost surely, 2^6856504381 is an apocalyptic number.

It is an amenable number.

6856504381 is a deficient number, since it is larger than the sum of its proper divisors (1).

6856504381 is an equidigital number, since it uses as much as digits as its factorization.

6856504381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 691200, while the sum is 46.

The square root of 6856504381 is about 82804.0118653680. The cubic root of 6856504381 is about 1899.7695363126.

The spelling of 6856504381 in words is "six billion, eight hundred fifty-six million, five hundred four thousand, three hundred eighty-one".