647623 has 4 divisors (see below), whose sum is σ = 662728. Its totient is φ = 632520.

The previous prime is 647617. The next prime is 647627. The reversal of 647623 is 326746.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 647623 - 2⁹ = 647111 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 647591 and 647600.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (647627) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 7488 + ... + 7573.

It is an arithmetic number, because the mean of its divisors is an integer number (165682).

2⁶⁴⁷⁶²³ is an apocalyptic number.

647623 is a deficient number, since it is larger than the sum of its proper divisors (15105).

647623 is a wasteful number, since it uses less digits than its factorization.

647623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15104.

The product of its digits is 6048, while the sum is 28.

The square root of 647623 is about 804.7502718235. The cubic root of 647623 is about 86.5181892318.

The spelling of 647623 in words is "six hundred forty-seven thousand, six hundred twenty-three".