646257223 has 4 divisors (see below), whose sum is σ = 648642208. Its totient is φ = 643872240.

The previous prime is 646257187. The next prime is 646257233. The reversal of 646257223 is 322752646.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 322752646 = 2 ⋅161376323.

It is a cyclic number.

It is not a de Polignac number, because 646257223 - 2¹³ = 646249031 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 (646257233) 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 3 ways as a sum of consecutive naturals, for example, 1192086 + ... + 1192627.

It is an arithmetic number, because the mean of its divisors is an integer number (162160552).

Almost surely, 2^646257223 is an apocalyptic number.

646257223 is a deficient number, since it is larger than the sum of its proper divisors (2384985).

646257223 is a wasteful number, since it uses less digits than its factorization.

646257223 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2384984.

The product of its digits is 120960, while the sum is 37.

The square root of 646257223 is about 25421.5897024557. The cubic root of 646257223 is about 864.5732680802.

The spelling of 646257223 in words is "six hundred forty-six million, two hundred fifty-seven thousand, two hundred twenty-three".