664565565451 has 2 divisors, whose sum is σ = 664565565452. Its totient is φ = 664565565450.

The previous prime is 664565565431. The next prime is 664565565467. The reversal of 664565565451 is 154565565466.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 664565565451 - 2³¹ = 662418081803 is a prime.

It is not a weakly prime, because it can be changed into another prime (664565565401) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 332282782725 + 332282782726.

It is an arithmetic number, because the mean of its divisors is an integer number (332282782726).

Almost surely, 2^664565565451 is an apocalyptic number.

664565565451 is a deficient number, since it is larger than the sum of its proper divisors (1).

664565565451 is an equidigital number, since it uses as much as digits as its factorization.

664565565451 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 64800000, while the sum is 58.

The spelling of 664565565451 in words is "six hundred sixty-four billion, five hundred sixty-five million, five hundred sixty-five thousand, four hundred fifty-one".