646472 has 8 divisors (see below), whose sum is σ = 1212150. Its totient is φ = 323232.

The previous prime is 646453. The next prime is 646519. The reversal of 646472 is 274646.

646472 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in only one way, i.e., 481636 + 164836 = 694^2 + 406^2 .

It is a tau number, because it is divible by the number of its divisors (8).

It is a nialpdrome in base 15.

It is an unprimeable number.

646472 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 40397 + ... + 40412.

2⁶⁴⁶⁴⁷² is an apocalyptic number.

It is an amenable number.

646472 is a deficient number, since it is larger than the sum of its proper divisors (565678).

646472 is a wasteful number, since it uses less digits than its factorization.

646472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 80815 (or 80811 counting only the distinct ones).

The product of its digits is 8064, while the sum is 29.

The square root of 646472 is about 804.0348251164. The cubic root of 646472 is about 86.4669034843.

The spelling of 646472 in words is "six hundred forty-six thousand, four hundred seventy-two".