646996 has 18 divisors (see below), whose sum is σ = 1317498. Its totient is φ = 277200.

The previous prime is 646993. The next prime is 647011. The reversal of 646996 is 699646.

It can be written as a sum of positive squares in only one way, i.e., 470596 + 176400 = 686^2 + 420^2 .

It is a nialpdrome in base 7 and base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (646991) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 1455 + ... + 1846.

2⁶⁴⁶⁹⁹⁶ is an apocalyptic number.

It is an amenable number.

646996 is an abundant number, since it is smaller than the sum of its proper divisors (670502).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

646996 is a wasteful number, since it uses less digits than its factorization.

646996 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3319 (or 3310 counting only the distinct ones).

The product of its digits is 69984, while the sum is 40.

The square root of 646996 is about 804.3606156445. The cubic root of 646996 is about 86.4902591858.

Subtracting 646996 from its reverse (699646), we obtain a triangular number (52650 = T₃₂₄).

It can be divided in two parts, 64 and 6996, that multiplied together give a palindrome (447744).

The spelling of 646996 in words is "six hundred forty-six thousand, nine hundred ninety-six".