6224720613721 has 9 divisors (see below), whose sum is σ = 6247967334399. Its totient is φ = 6201560094984.

The previous prime is 6224720613691. The next prime is 6224720613737. The reversal of 6224720613721 is 1273160274226.

The square root of 6224720613721 is 2494939.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1072891998025 + 5151828615696 = 1035805^2 + 2269764^2 .

It is not a de Polignac number, because 6224720613721 - 2¹¹ = 6224720611673 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6224720613421) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 691093600 + ... + 691102606.

It is an arithmetic number, because the mean of its divisors is an integer number (694218592711).

Almost surely, 2^{6224720613721} is an apocalyptic number.

6224720613721 is the 2494939-th square number.

6224720613721 is the 1247470-th centered octagonal number.

It is an amenable number.

6224720613721 is a deficient number, since it is larger than the sum of its proper divisors (23246720678).

6224720613721 is an frugal number, since it uses more digits than its factorization.

6224720613721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 18568 (or 9284 counting only the distinct ones).

The product of its (nonzero) digits is 338688, while the sum is 43.

Adding to 6224720613721 its reverse (1273160274226), we get a palindrome (7497880887947).

The spelling of 6224720613721 in words is "six trillion, two hundred twenty-four billion, seven hundred twenty million, six hundred thirteen thousand, seven hundred twenty-one".