6457664261 has 4 divisors (see below), whose sum is σ = 6458403852. Its totient is φ = 6456924672.

The previous prime is 6457664249. The next prime is 6457664267. The reversal of 6457664261 is 1624667546.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1624667546 = 2 ⋅812333773.

It can be written as a sum of positive squares in 2 ways, for example, as 6101172100 + 356492161 = 78110^2 + 18881^2 .

It is a cyclic number.

It is not a de Polignac number, because 6457664261 - 2¹⁰ = 6457663237 is a prime.

It is a super-2 number, since 2×6457664261² = 83402855415593352242, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (6457664267) 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, 356540 + ... + 374213.

It is an arithmetic number, because the mean of its divisors is an integer number (1614600963).

Almost surely, 2^6457664261 is an apocalyptic number.

It is an amenable number.

6457664261 is a deficient number, since it is larger than the sum of its proper divisors (739591).

6457664261 is an equidigital number, since it uses as much as digits as its factorization.

6457664261 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 739590.

The product of its digits is 1451520, while the sum is 47.

The square root of 6457664261 is about 80359.5934596486. The cubic root of 6457664261 is about 1862.1949903728.

The spelling of 6457664261 in words is "six billion, four hundred fifty-seven million, six hundred sixty-four thousand, two hundred sixty-one".