6541620345 has 80 divisors (see below), whose sum is σ = 12759682320. Its totient is φ = 3187040256.

The previous prime is 6541620343. The next prime is 6541620361. The reversal of 6541620345 is 5430261456.

It can be written as a sum of positive squares in 8 ways, for example, as 929213289 + 5612407056 = 30483^2 + 74916^2 .

It is not a de Polignac number, because 6541620345 - 2¹ = 6541620343 is a prime.

It is not an unprimeable number, because it can be changed into a prime (6541620343) by changing a digit.

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 79 ways as a sum of consecutive naturals, for example, 504301 + ... + 517109.

It is an arithmetic number, because the mean of its divisors is an integer number (159496029).

Almost surely, 2^6541620345 is an apocalyptic number.

6541620345 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

6541620345 is a deficient number, since it is larger than the sum of its proper divisors (6218061975).

6541620345 is a wasteful number, since it uses less digits than its factorization.

6541620345 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12936 (or 12927 counting only the distinct ones).

The product of its (nonzero) digits is 86400, while the sum is 36.

The square root of 6541620345 is about 80880.2840314004. The cubic root of 6541620345 is about 1870.2303990380.

The spelling of 6541620345 in words is "six billion, five hundred forty-one million, six hundred twenty thousand, three hundred forty-five".