646953 has 8 divisors (see below), whose sum is σ = 866400. Its totient is φ = 429408.

The previous prime is 646937. The next prime is 646957. The reversal of 646953 is 359646.

It is a happy number.

646953 is a nontrivial binomial coefficient, being equal to C(1138, 2).

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

It is not a de Polignac number, because 646953 - 2⁴ = 646937 is a prime.

It is a nialpdrome in base 15.

It is a congruent number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 646953.

It is not an unprimeable number, because it can be changed into a prime (646957) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 853 + ... + 1421.

It is an arithmetic number, because the mean of its divisors is an integer number (108300).

2⁶⁴⁶⁹⁵³ is an apocalyptic number.

646953 is the 1137-th triangular number and also the 569-th hexagonal number.

It is an amenable number.

646953 is a deficient number, since it is larger than the sum of its proper divisors (219447).

646953 is a wasteful number, since it uses less digits than its factorization.

646953 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 951.

The product of its digits is 19440, while the sum is 33.

The square root of 646953 is about 804.3338858957. Note that the first 3 decimals coincide. The cubic root of 646953 is about 86.4883430670.

The spelling of 646953 in words is "six hundred forty-six thousand, nine hundred fifty-three".