667390121 has 2 divisors, whose sum is σ = 667390122. Its totient is φ = 667390120.

The previous prime is 667390093. The next prime is 667390133. The reversal of 667390121 is 121093766.

667390121 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 547794025 + 119596096 = 23405^2 + 10936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-667390121 is a prime.

It is not a weakly prime, because it can be changed into another prime (667390921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 333695060 + 333695061.

It is an arithmetic number, because the mean of its divisors is an integer number (333695061).

Almost surely, 2^667390121 is an apocalyptic number.

It is an amenable number.

667390121 is a deficient number, since it is larger than the sum of its proper divisors (1).

667390121 is an equidigital number, since it uses as much as digits as its factorization.

667390121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 13608, while the sum is 35.

The square root of 667390121 is about 25833.8948089521. The cubic root of 667390121 is about 873.8963482865.

The spelling of 667390121 in words is "six hundred sixty-seven million, three hundred ninety thousand, one hundred twenty-one".