647249 has 4 divisors (see below), whose sum is σ = 668160. Its totient is φ = 626340.

The previous prime is 647219. The next prime is 647261. The reversal of 647249 is 942746.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 647249 - 2⁸ = 646993 is a prime.

It is a Duffinian number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 647249.

It is not an unprimeable number, because it can be changed into a prime (647209) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10409 + ... + 10470.

It is an arithmetic number, because the mean of its divisors is an integer number (167040).

2⁶⁴⁷²⁴⁹ is an apocalyptic number.

It is an amenable number.

647249 is a deficient number, since it is larger than the sum of its proper divisors (20911).

647249 is a wasteful number, since it uses less digits than its factorization.

647249 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20910.

The product of its digits is 12096, while the sum is 32.

The square root of 647249 is about 804.5178680427. The cubic root of 647249 is about 86.5015313750.

The spelling of 647249 in words is "six hundred forty-seven thousand, two hundred forty-nine".