6561326641320 has 96 divisors (see below), whose sum is σ = 23262885378720. Its totient is φ = 1590624639360.

The previous prime is 6561326641273. The next prime is 6561326641321. The reversal of 6561326641320 is 231466231656.

6561326641320 is a `hidden beast` number, since 6 + 5 + 61 + 3 + 266 + 4 + 1 + 320 = 666.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is not an unprimeable number, because it can be changed into a prime (6561326641321) 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 23 ways as a sum of consecutive naturals, for example, 828446374 + ... + 828454293.

It is an arithmetic number, because the mean of its divisors is an integer number (242321722695).

Almost surely, 2^{6561326641320} is an apocalyptic number.

6561326641320 is a gapful number since it is divisible by the number (60) formed by its first and last digit.

It is an amenable number.

6561326641320 is an abundant number, since it is smaller than the sum of its proper divisors (16701558737400).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6561326641320 is a wasteful number, since it uses less digits than its factorization.

6561326641320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1656900695 (or 1656900688 counting only the distinct ones).

The product of its (nonzero) digits is 933120, while the sum is 45.

The spelling of 6561326641320 in words is "six trillion, five hundred sixty-one billion, three hundred twenty-six million, six hundred forty-one thousand, three hundred twenty".