646471 has 4 divisors (see below), whose sum is σ = 738832. Its totient is φ = 554112.

The previous prime is 646453. The next prime is 646519. The reversal of 646471 is 174646.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 174646 = 2 ⋅87323.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-646471 is a prime.

It is a super-3 number, since 3×646471³ = 810528700621035333, which contains 333 as substring.

It is a Duffinian number.

It is a nialpdrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646411) 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, 46170 + ... + 46183.

It is an arithmetic number, because the mean of its divisors is an integer number (184708).

2⁶⁴⁶⁴⁷¹ is an apocalyptic number.

646471 is a deficient number, since it is larger than the sum of its proper divisors (92361).

646471 is an equidigital number, since it uses as much as digits as its factorization.

646471 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 92360.

The product of its digits is 4032, while the sum is 28.

The square root of 646471 is about 804.0342032526. The cubic root of 646471 is about 86.4668589002.

The spelling of 646471 in words is "six hundred forty-six thousand, four hundred seventy-one".