6657440401 has 2 divisors, whose sum is σ = 6657440402. Its totient is φ = 6657440400.

The previous prime is 6657440393. The next prime is 6657440411. The reversal of 6657440401 is 1040447566.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 6122906001 + 534534400 = 78249^2 + 23120^2 .

It is a cyclic number.

It is not a de Polignac number, because 6657440401 - 2³ = 6657440393 is a prime.

It is not a weakly prime, because it can be changed into another prime (6657440411) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3328720200 + 3328720201.

It is an arithmetic number, because the mean of its divisors is an integer number (3328720201).

Almost surely, 2^6657440401 is an apocalyptic number.

It is an amenable number.

6657440401 is a deficient number, since it is larger than the sum of its proper divisors (1).

6657440401 is an equidigital number, since it uses as much as digits as its factorization.

6657440401 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 80640, while the sum is 37.

The square root of 6657440401 is about 81593.1394236060. The cubic root of 6657440401 is about 1881.2034320897.

Adding to 6657440401 its reverse (1040447566), we get a palindrome (7697887967).

The spelling of 6657440401 in words is "six billion, six hundred fifty-seven million, four hundred forty thousand, four hundred one".