668888233121 has 2 divisors, whose sum is σ = 668888233122. Its totient is φ = 668888233120.

The previous prime is 668888233103. The next prime is 668888233133. The reversal of 668888233121 is 121332888866.

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., 579151440400 + 89736792721 = 761020^2 + 299561^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-668888233121 is a prime.

It is a super-2 number, since 2×668888233121² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (668888233721) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334444116560 + 334444116561.

It is an arithmetic number, because the mean of its divisors is an integer number (334444116561).

Almost surely, 2^668888233121 is an apocalyptic number.

It is an amenable number.

668888233121 is a deficient number, since it is larger than the sum of its proper divisors (1).

668888233121 is an equidigital number, since it uses as much as digits as its factorization.

668888233121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 5308416, while the sum is 56.

The spelling of 668888233121 in words is "six hundred sixty-eight billion, eight hundred eighty-eight million, two hundred thirty-three thousand, one hundred twenty-one".