646774 has 8 divisors (see below), whose sum is σ = 974088. Its totient is φ = 322080.

The previous prime is 646771. The next prime is 646781. The reversal of 646774 is 477646.

It is a sphenic number, since it is the product of 3 distinct primes.

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 (646771) 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, 174 + ... + 1150.

It is an arithmetic number, because the mean of its divisors is an integer number (121761).

2⁶⁴⁶⁷⁷⁴ is an apocalyptic number.

646774 is a deficient number, since it is larger than the sum of its proper divisors (327314).

646774 is a wasteful number, since it uses less digits than its factorization.

646774 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1310.

The product of its digits is 28224, while the sum is 34.

The square root of 646774 is about 804.2226059991. Note that the first 3 decimals coincide. The cubic root of 646774 is about 86.4803657531.

The spelling of 646774 in words is "six hundred forty-six thousand, seven hundred seventy-four".