6457086721 has 4 divisors (see below), whose sum is σ = 6457842112. Its totient is φ = 6456331332.

The previous prime is 6457086719. The next prime is 6457086733. The reversal of 6457086721 is 1276807546.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 6457086721 - 2¹ = 6457086719 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (6457081721) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 364725 + ... + 382018.

It is an arithmetic number, because the mean of its divisors is an integer number (1614460528).

Almost surely, 2^6457086721 is an apocalyptic number.

It is an amenable number.

6457086721 is a deficient number, since it is larger than the sum of its proper divisors (755391).

6457086721 is an equidigital number, since it uses as much as digits as its factorization.

6457086721 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 755390.

The product of its (nonzero) digits is 564480, while the sum is 46.

The square root of 6457086721 is about 80355.9999066653. Note that the first 4 decimals coincide. The cubic root of 6457086721 is about 1862.1394736970.

The spelling of 6457086721 in words is "six billion, four hundred fifty-seven million, eighty-six thousand, seven hundred twenty-one".