647985 has 16 divisors (see below), whose sum is σ = 1116864. Its totient is φ = 318912.

The previous prime is 647963. The next prime is 647987. The reversal of 647985 is 589746.

647985 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 647985 - 2⁵ = 647953 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (39).

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 647985.

It is not an unprimeable number, because it can be changed into a prime (647987) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1467 + ... + 1856.

It is an arithmetic number, because the mean of its divisors is an integer number (69804).

2⁶⁴⁷⁹⁸⁵ is an apocalyptic number.

647985 is a gapful number since it is divisible by the number (65) formed by its first and last digit.

It is an amenable number.

647985 is a deficient number, since it is larger than the sum of its proper divisors (468879).

647985 is a wasteful number, since it uses less digits than its factorization.

647985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3344.

The product of its digits is 60480, while the sum is 39.

The square root of 647985 is about 804.9751548961. The cubic root of 647985 is about 86.5343065052.

The spelling of 647985 in words is "six hundred forty-seven thousand, nine hundred eighty-five".