647665543 has 8 divisors (see below), whose sum is σ = 747107712. Its totient is φ = 549953016.

The previous prime is 647665537. The next prime is 647665607. The reversal of 647665543 is 345566746.

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 647665543 - 2²⁹ = 110794631 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 647665493 and 647665502.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647663543) 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, 431605 + ... + 433102.

It is an arithmetic number, because the mean of its divisors is an integer number (93388464).

Almost surely, 2^647665543 is an apocalyptic number.

647665543 is a deficient number, since it is larger than the sum of its proper divisors (99442169).

647665543 is a wasteful number, since it uses less digits than its factorization.

647665543 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 864821.

The product of its digits is 1814400, while the sum is 46.

The square root of 647665543 is about 25449.2739189156. The cubic root of 647665543 is about 865.2008367900.

The spelling of 647665543 in words is "six hundred forty-seven million, six hundred sixty-five thousand, five hundred forty-three".