6438623 has 4 divisors (see below), whose sum is σ = 6443808. Its totient is φ = 6433440.

The previous prime is 6438617. The next prime is 6438637. The reversal of 6438623 is 3268346.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-6438623 is a prime.

It is a super-2 number, since 2×6438623² = 82911732272258, which contains 22 as substring.

It is a Duffinian number.

Its product of digits (20736) is a multiple of the sum of its prime divisors (5184).

It is a self number, because there is not a number n which added to its sum of digits gives 6438623.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6438923) 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, 503 + ... + 3623.

It is an arithmetic number, because the mean of its divisors is an integer number (1610952).

Almost surely, 2^6438623 is an apocalyptic number.

6438623 is a deficient number, since it is larger than the sum of its proper divisors (5185).

6438623 is a wasteful number, since it uses less digits than its factorization.

6438623 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5184.

The product of its digits is 20736, while the sum is 32.

The square root of 6438623 is about 2537.4441865783. Note that the first 3 decimals coincide. The cubic root of 6438623 is about 186.0362880599.

The spelling of 6438623 in words is "six million, four hundred thirty-eight thousand, six hundred twenty-three".