65651551660609 has 2 divisors, whose sum is σ = 65651551660610. Its totient is φ = 65651551660608.

The previous prime is 65651551660577. The next prime is 65651551660613. The reversal of 65651551660609 is 90606615515656.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 38325422707009 + 27326128953600 = 6190753^2 + 5227440^2 .

It is a cyclic number.

It is not a de Polignac number, because 65651551660609 - 2⁵ = 65651551660577 is a prime.

It is a super-2 number, since 2×65651551660609² (a number of 28 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (65651551660649) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 32825775830304 + 32825775830305.

It is an arithmetic number, because the mean of its divisors is an integer number (32825775830305).

Almost surely, 2^{65651551660609} is an apocalyptic number.

It is an amenable number.

65651551660609 is a deficient number, since it is larger than the sum of its proper divisors (1).

65651551660609 is an equidigital number, since it uses as much as digits as its factorization.

65651551660609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 43740000, while the sum is 61.

The spelling of 65651551660609 in words is "sixty-five trillion, six hundred fifty-one billion, five hundred fifty-one million, six hundred sixty thousand, six hundred nine".