6646540433 has 4 divisors (see below), whose sum is σ = 7157812788. Its totient is φ = 6135268080.

The previous prime is 6646540403. The next prime is 6646540451. The reversal of 6646540433 is 3340456466.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 1159879249 + 5486661184 = 34057^2 + 74072^2 .

It is a cyclic number.

It is not a de Polignac number, because 6646540433 - 2¹⁰ = 6646539409 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6646540403) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 255636158 + ... + 255636183.

It is an arithmetic number, because the mean of its divisors is an integer number (1789453197).

Almost surely, 2^6646540433 is an apocalyptic number.

It is an amenable number.

6646540433 is a deficient number, since it is larger than the sum of its proper divisors (511272355).

6646540433 is a wasteful number, since it uses less digits than its factorization.

6646540433 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 511272354.

The product of its (nonzero) digits is 622080, while the sum is 41.

The square root of 6646540433 is about 81526.3174257246. The cubic root of 6646540433 is about 1880.1761975533.

Adding to 6646540433 its reverse (3340456466), we get a palindrome (9986996899).

The spelling of 6646540433 in words is "six billion, six hundred forty-six million, five hundred forty thousand, four hundred thirty-three".