64662525661 has 2 divisors, whose sum is σ = 64662525662. Its totient is φ = 64662525660.

The previous prime is 64662525617. The next prime is 64662525691. The reversal of 64662525661 is 16652526646.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 59650735225 + 5011790436 = 244235^2 + 70794^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-64662525661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (64662525601) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32331262830 + 32331262831.

It is an arithmetic number, because the mean of its divisors is an integer number (32331262831).

Almost surely, 2^64662525661 is an apocalyptic number.

It is an amenable number.

64662525661 is a deficient number, since it is larger than the sum of its proper divisors (1).

64662525661 is an equidigital number, since it uses as much as digits as its factorization.

64662525661 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3110400, while the sum is 49.

The spelling of 64662525661 in words is "sixty-four billion, six hundred sixty-two million, five hundred twenty-five thousand, six hundred sixty-one".