6940721 has 4 divisors (see below), whose sum is σ = 7071732. Its totient is φ = 6809712.

The previous prime is 6940711. The next prime is 6940723. The reversal of 6940721 is 1270496.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2676496 + 4264225 = 1636^2 + 2065^2 .

It is a cyclic number.

It is not a de Polignac number, because 6940721 - 2¹⁰ = 6939697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6940723) 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, 65426 + ... + 65531.

It is an arithmetic number, because the mean of its divisors is an integer number (1767933).

Almost surely, 2^6940721 is an apocalyptic number.

It is an amenable number.

6940721 is a deficient number, since it is larger than the sum of its proper divisors (131011).

6940721 is a wasteful number, since it uses less digits than its factorization.

6940721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 131010.

The product of its (nonzero) digits is 3024, while the sum is 29.

The square root of 6940721 is about 2634.5248148385. The cubic root of 6940721 is about 190.7516027571.

The spelling of 6940721 in words is "six million, nine hundred forty thousand, seven hundred twenty-one".