6520661543 has 8 divisors (see below), whose sum is σ = 7115644800. Its totient is φ = 5926044280.

The previous prime is 6520661531. The next prime is 6520661557. The reversal of 6520661543 is 3451660256.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 6520661543 - 2¹² = 6520657447 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 6520661497 and 6520661506.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6520661503) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 53555 + ... + 126132.

It is an arithmetic number, because the mean of its divisors is an integer number (889455600).

Almost surely, 2^6520661543 is an apocalyptic number.

6520661543 is a deficient number, since it is larger than the sum of its proper divisors (594983257).

6520661543 is a wasteful number, since it uses less digits than its factorization.

6520661543 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 182997.

The product of its (nonzero) digits is 129600, while the sum is 38.

The square root of 6520661543 is about 80750.6132670211. The cubic root of 6520661543 is about 1868.2309084240.

The spelling of 6520661543 in words is "six billion, five hundred twenty million, six hundred sixty-one thousand, five hundred forty-three".