667765122001 has 2 divisors, whose sum is σ = 667765122002. Its totient is φ = 667765122000.

The previous prime is 667765121999. The next prime is 667765122047. The reversal of 667765122001 is 100221567766.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 577028621376 + 90736500625 = 759624^2 + 301225^2 .

It is a cyclic number.

It is not a de Polignac number, because 667765122001 - 2¹ = 667765121999 is a prime.

It is a super-2 number, since 2×667765122001² (a number of 24 digits) contains 22 as substring.

Together with 667765121999, it forms a pair of twin primes.

It is not a weakly prime, because it can be changed into another prime (667765122061) 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, 333882561000 + 333882561001.

It is an arithmetic number, because the mean of its divisors is an integer number (333882561001).

Almost surely, 2^667765122001 is an apocalyptic number.

It is an amenable number.

667765122001 is a deficient number, since it is larger than the sum of its proper divisors (1).

667765122001 is an equidigital number, since it uses as much as digits as its factorization.

667765122001 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 211680, while the sum is 43.

Adding to 667765122001 its reverse (100221567766), we get a palindrome (767986689767).

The spelling of 667765122001 in words is "six hundred sixty-seven billion, seven hundred sixty-five million, one hundred twenty-two thousand, one".