165220626543649 has 2 divisors, whose sum is σ = 165220626543650. Its totient is φ = 165220626543648.

The previous prime is 165220626543491. The next prime is 165220626543683. The reversal of 165220626543649 is 946345626022561.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 93359944667025 + 71860681876624 = 9662295^2 + 8477068^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-165220626543649 is a prime.

It is not a weakly prime, because it can be changed into another prime (165220626543149) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 82610313271824 + 82610313271825.

It is an arithmetic number, because the mean of its divisors is an integer number (82610313271825).

Almost surely, 2^{165220626543649} is an apocalyptic number.

It is an amenable number.

165220626543649 is a deficient number, since it is larger than the sum of its proper divisors (1).

165220626543649 is an equidigital number, since it uses as much as digits as its factorization.

165220626543649 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 111974400, while the sum is 61.

The spelling of 165220626543649 in words is "one hundred sixty-five trillion, two hundred twenty billion, six hundred twenty-six million, five hundred forty-three thousand, six hundred forty-nine".