6725721220 has 24 divisors (see below), whose sum is σ = 14954839704. Its totient is φ = 2532036096.

The previous prime is 6725721217. The next prime is 6725721229. The reversal of 6725721220 is 221275276.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 753831936 + 5971889284 = 27456^2 + 77278^2 .

It is a Harshad number since it is a multiple of its sum of digits (34).

It is not an unprimeable number, because it can be changed into a prime (6725721229) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9890427 + ... + 9891106.

It is an arithmetic number, because the mean of its divisors is an integer number (623118321).

Almost surely, 2^6725721220 is an apocalyptic number.

It is an amenable number.

6725721220 is an abundant number, since it is smaller than the sum of its proper divisors (8229118484).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

6725721220 is a wasteful number, since it uses less digits than its factorization.

6725721220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19781559 (or 19781557 counting only the distinct ones).

The product of its (nonzero) digits is 23520, while the sum is 34.

The square root of 6725721220 is about 82010.4945723412. The cubic root of 6725721220 is about 1887.6129752415.

Adding to 6725721220 its reverse (221275276), we get a palindrome (6946996496).

The spelling of 6725721220 in words is "six billion, seven hundred twenty-five million, seven hundred twenty-one thousand, two hundred twenty".