6396881555 has 8 divisors (see below), whose sum is σ = 8010008352. Its totient is φ = 4895004928.

The previous prime is 6396881549. The next prime is 6396881593. The reversal of 6396881555 is 5551886936.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6396881555 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6396881555.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 27812414 + ... + 27812643.

It is an arithmetic number, because the mean of its divisors is an integer number (1001251044).

Almost surely, 2^6396881555 is an apocalyptic number.

6396881555 is a deficient number, since it is larger than the sum of its proper divisors (1613126797).

6396881555 is a wasteful number, since it uses less digits than its factorization.

6396881555 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55625085.

The product of its digits is 7776000, while the sum is 56.

The square root of 6396881555 is about 79980.5073439773. The cubic root of 6396881555 is about 1856.3339315479. Note that the first 3 decimals are identical.

The spelling of 6396881555 in words is "six billion, three hundred ninety-six million, eight hundred eighty-one thousand, five hundred fifty-five".