646559423 has 4 divisors (see below), whose sum is σ = 664034040. Its totient is φ = 629084808.

The previous prime is 646559411. The next prime is 646559429. The reversal of 646559423 is 324955646.

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 646559423 - 2²⁴ = 629782207 is a prime.

It is a super-3 number, since 3×646559423³ (a number of 27 digits) contains 333 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646559429) 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, 8737253 + ... + 8737326.

It is an arithmetic number, because the mean of its divisors is an integer number (166008510).

Almost surely, 2^646559423 is an apocalyptic number.

646559423 is a deficient number, since it is larger than the sum of its proper divisors (17474617).

646559423 is a wasteful number, since it uses less digits than its factorization.

646559423 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17474616.

The product of its digits is 777600, while the sum is 44.

The square root of 646559423 is about 25427.5327745340. The cubic root of 646559423 is about 864.7080097473.

The spelling of 646559423 in words is "six hundred forty-six million, five hundred fifty-nine thousand, four hundred twenty-three".