6720505 has 16 divisors (see below), whose sum is σ = 8926848. Its totient is φ = 4816000.

The previous prime is 6720503. The next prime is 6720517. The reversal of 6720505 is 5050276.

It is a happy number.

It is not a de Polignac number, because 6720505 - 2¹ = 6720503 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 6720505.

It is not an unprimeable number, because it can be changed into a prime (6720503) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3045 + ... + 4765.

It is an arithmetic number, because the mean of its divisors is an integer number (557928).

Almost surely, 2^6720505 is an apocalyptic number.

It is an amenable number.

6720505 is a deficient number, since it is larger than the sum of its proper divisors (2206343).

6720505 is a wasteful number, since it uses less digits than its factorization.

6720505 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1808.

The product of its (nonzero) digits is 2100, while the sum is 25.

The square root of 6720505 is about 2592.3936815229. The cubic root of 6720505 is about 188.7124861487.

It can be divided in two parts, 6720 and 505, that added together give a square (7225 = 85²).

The spelling of 6720505 in words is "six million, seven hundred twenty thousand, five hundred five".