6720643 has 4 divisors (see below), whose sum is σ = 6902320. Its totient is φ = 6538968.

The previous prime is 6720629. The next prime is 6720667. The reversal of 6720643 is 3460276.

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 6720643 - 2¹³ = 6712451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6720673) 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, 90783 + ... + 90856.

It is an arithmetic number, because the mean of its divisors is an integer number (1725580).

Almost surely, 2^6720643 is an apocalyptic number.

6720643 is a deficient number, since it is larger than the sum of its proper divisors (181677).

6720643 is a wasteful number, since it uses less digits than its factorization.

6720643 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 181676.

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

The square root of 6720643 is about 2592.4202977141. The cubic root of 6720643 is about 188.7137778247.

The spelling of 6720643 in words is "six million, seven hundred twenty thousand, six hundred forty-three".