6723649 has 3 divisors (see below), whose sum is σ = 6726243. Its totient is φ = 6721056.

The previous prime is 6723643. The next prime is 6723667. The reversal of 6723649 is 9463276.

The square root of 6723649 is 2593.

It is a perfect power (a square), and thus also a powerful number.

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 can be written as a sum of positive squares in only one way, i.e., 4060225 + 2663424 = 2015^2 + 1632^2 .

It is not a de Polignac number, because 6723649 - 2³ = 6723641 is a prime.

It is a d-powerful number, because it can be written as 6 + 7⁸ + 2¹⁷ + 3¹² + 6⁷ + 4⁷ + 9 .

It is a Duffinian number.

6723649 is a lucky number.

It is not an unprimeable number, because it can be changed into a prime (6723641) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 1297 + ... + 3889.

It is an arithmetic number, because the mean of its divisors is an integer number (2242081).

Almost surely, 2^6723649 is an apocalyptic number.

6723649 is the 2593-rd square number.

6723649 is the 1297-th centered octagonal number.

It is an amenable number.

6723649 is a deficient number, since it is larger than the sum of its proper divisors (2594).

6723649 is an frugal number, since it uses more digits than its factorization.

6723649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5186 (or 2593 counting only the distinct ones).

The product of its digits is 54432, while the sum is 37.

The cubic root of 6723649 is about 188.7419095110.

It can be divided in two parts, 67 and 23649, that added together give a square (23716 = 154²).

The spelling of 6723649 in words is "six million, seven hundred twenty-three thousand, six hundred forty-nine".