6396554197881 has 81 divisors (see below), whose sum is σ = 9933306136429. Its totient is φ = 3965693088000.

The previous prime is 6396554197871. The next prime is 6396554197897. The reversal of 6396554197881 is 1887914556936.

The square root of 6396554197881 is 2529141.

It is a perfect power (a square), and thus also a powerful number.

6396554197881 is a `hidden beast` number, since 6 + 3 + 9 + 6 + 5 + 541 + 9 + 78 + 8 + 1 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 3809230475625 + 2587323722256 = 1951725^2 + 1608516^2 .

It is not a de Polignac number, because 6396554197881 - 2²⁵ = 6396520643449 is a prime.

It is a super-2 number, since 2×6396554197881² (a number of 26 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6396554197871) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 80 ways as a sum of consecutive naturals, for example, 13027605046 + ... + 13027605536.

Almost surely, 2^{6396554197881} is an apocalyptic number.

6396554197881 is the 2529141-st square number.

6396554197881 is the 1264571-st centered octagonal number.

It is an amenable number.

6396554197881 is a deficient number, since it is larger than the sum of its proper divisors (3536751938548).

6396554197881 is an equidigital number, since it uses as much as digits as its factorization.

6396554197881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1224 (or 612 counting only the distinct ones).

The product of its digits is 391910400, while the sum is 72.

The spelling of 6396554197881 in words is "six trillion, three hundred ninety-six billion, five hundred fifty-four million, one hundred ninety-seven thousand, eight hundred eighty-one".