646423173 has 40 divisors (see below), whose sum is σ = 1066244256. Its totient is φ = 387007200.

The previous prime is 646423163. The next prime is 646423213. The reversal of 646423173 is 371324646.

It is a happy number.

646423173 is a `hidden beast` number, since 6 + 4 + 642 + 3 + 1 + 7 + 3 = 666.

It is not a de Polignac number, because 646423173 - 2⁹ = 646422661 is a prime.

It is a hoax number, since the sum of its digits (36) coincides with the sum of the digits of its distinct prime factors.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646423163) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 69583 + ... + 78323.

Almost surely, 2^646423173 is an apocalyptic number.

It is an amenable number.

646423173 is a deficient number, since it is larger than the sum of its proper divisors (419821083).

646423173 is a wasteful number, since it uses less digits than its factorization.

646423173 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8847 (or 8838 counting only the distinct ones).

The product of its digits is 72576, while the sum is 36.

The square root of 646423173 is about 25424.8534509051. The cubic root of 646423173 is about 864.6472652697.

The spelling of 646423173 in words is "six hundred forty-six million, four hundred twenty-three thousand, one hundred seventy-three".