646423172 has 12 divisors (see below), whose sum is σ = 1132326300. Its totient is φ = 322901376.

The previous prime is 646423163. The next prime is 646423213. The reversal of 646423172 is 271324646.

It can be written as a sum of positive squares in 2 ways, for example, as 405055876 + 241367296 = 20126^2 + 15536^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 72833 + ... + 81224.

It is an arithmetic number, because the mean of its divisors is an integer number (94360525).

Almost surely, 2^646423172 is an apocalyptic number.

It is an amenable number.

646423172 is a deficient number, since it is larger than the sum of its proper divisors (485903128).

646423172 is a wasteful number, since it uses less digits than its factorization.

646423172 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 155110 (or 155108 counting only the distinct ones).

The product of its digits is 48384, while the sum is 35.

The square root of 646423172 is about 25424.8534312393. The cubic root of 646423172 is about 864.6472648239.

The spelling of 646423172 in words is "six hundred forty-six million, four hundred twenty-three thousand, one hundred seventy-two".