646899 has 8 divisors (see below), whose sum is σ = 940992. Its totient is φ = 392040.

The previous prime is 646897. The next prime is 646909. The reversal of 646899 is 998646.

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

It is not a de Polignac number, because 646899 - 2¹ = 646897 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 646899.

It is not an unprimeable number, because it can be changed into a prime (646897) 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, 9769 + ... + 9834.

It is an arithmetic number, because the mean of its divisors is an integer number (117624).

2⁶⁴⁶⁸⁹⁹ is an apocalyptic number.

646899 is a deficient number, since it is larger than the sum of its proper divisors (294093).

646899 is a wasteful number, since it uses less digits than its factorization.

646899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 19617.

The product of its digits is 93312, while the sum is 42.

The square root of 646899 is about 804.3003170458. The cubic root of 646899 is about 86.4859366581.

The spelling of 646899 in words is "six hundred forty-six thousand, eight hundred ninety-nine".