668347513481 has 2 divisors, whose sum is σ = 668347513482. Its totient is φ = 668347513480.

The previous prime is 668347513451. The next prime is 668347513511. The reversal of 668347513481 is 184315743866.

It is a happy number.

It is a balanced prime because it is at equal distance from previous prime (668347513451) and next prime (668347513511).

It can be written as a sum of positive squares in only one way, i.e., 429706470400 + 238641043081 = 655520^2 + 488509^2 .

It is a cyclic number.

It is not a de Polignac number, because 668347513481 - 2²² = 668343319177 is a prime.

It is a super-2 number, since 2×668347513481² (a number of 24 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (668347513451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334173756740 + 334173756741.

It is an arithmetic number, because the mean of its divisors is an integer number (334173756741).

Almost surely, 2^668347513481 is an apocalyptic number.

It is an amenable number.

668347513481 is a deficient number, since it is larger than the sum of its proper divisors (1).

668347513481 is an equidigital number, since it uses as much as digits as its factorization.

668347513481 is an evil number, because the sum of its binary digits is even.

The product of its digits is 11612160, while the sum is 56.

The spelling of 668347513481 in words is "six hundred sixty-eight billion, three hundred forty-seven million, five hundred thirteen thousand, four hundred eighty-one".