646044043 has 4 divisors (see below), whose sum is σ = 648890280. Its totient is φ = 643197808.

The previous prime is 646044031. The next prime is 646044073. The reversal of 646044043 is 340440646.

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

It is a cyclic number.

It is not a de Polignac number, because 646044043 - 2²⁹ = 109173131 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 646043996 and 646044014.

It is not an unprimeable number, because it can be changed into a prime (646044073) 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, 1422778 + ... + 1423231.

It is an arithmetic number, because the mean of its divisors is an integer number (162222570).

Almost surely, 2^646044043 is an apocalyptic number.

646044043 is a deficient number, since it is larger than the sum of its proper divisors (2846237).

646044043 is a wasteful number, since it uses less digits than its factorization.

646044043 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2846236.

The product of its (nonzero) digits is 27648, while the sum is 31.

The square root of 646044043 is about 25417.3964638395. The cubic root of 646044043 is about 864.4781924186.

Adding to 646044043 its reverse (340440646), we get a palindrome (986484689).

The spelling of 646044043 in words is "six hundred forty-six million, forty-four thousand, forty-three".