6940722721 has 3 divisors (see below), whose sum is σ = 6940806033. Its totient is φ = 6940639410.

The previous prime is 6940722713. The next prime is 6940722731. The reversal of 6940722721 is 1272270496.

The square root of 6940722721 is 83311.

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 is not a de Polignac number, because 6940722721 - 2³ = 6940722713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6940722731) 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, 41656 + ... + 124966.

It is an arithmetic number, because the mean of its divisors is an integer number (2313602011).

Almost surely, 2^6940722721 is an apocalyptic number.

6940722721 is the 83311-st square number.

6940722721 is the 41656-th centered octagonal number.

It is an amenable number.

6940722721 is a deficient number, since it is larger than the sum of its proper divisors (83312).

6940722721 is an frugal number, since it uses more digits than its factorization.

6940722721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 166622 (or 83311 counting only the distinct ones).

The product of its (nonzero) digits is 84672, while the sum is 40.

The cubic root of 6940722721 is about 1907.5161852315.

The spelling of 6940722721 in words is "six billion, nine hundred forty million, seven hundred twenty-two thousand, seven hundred twenty-one".