646424263 has 4 divisors (see below), whose sum is σ = 646857000. Its totient is φ = 645991528.

The previous prime is 646424243. The next prime is 646424279. The reversal of 646424263 is 362424646.

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 646424263 - 2⁵ = 646424231 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646424243) 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, 214120 + ... + 217117.

It is an arithmetic number, because the mean of its divisors is an integer number (161714250).

Almost surely, 2^646424263 is an apocalyptic number.

646424263 is a deficient number, since it is larger than the sum of its proper divisors (432737).

646424263 is a wasteful number, since it uses less digits than its factorization.

646424263 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 432736.

The product of its digits is 165888, while the sum is 37.

The square root of 646424263 is about 25424.8748866145. The cubic root of 646424263 is about 864.6477512594.

The spelling of 646424263 in words is "six hundred forty-six million, four hundred twenty-four thousand, two hundred sixty-three".