669121 has 2 divisors, whose sum is σ = 669122. Its totient is φ = 669120.

The previous prime is 669113. The next prime is 669127. The reversal of 669121 is 121966.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 579121 + 90000 = 761^2 + 300^2 .

It is a cyclic number.

It is not a de Polignac number, because 669121 - 2³ = 669113 is a prime.

It is not a weakly prime, because it can be changed into another prime (669127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 334560 + 334561.

It is an arithmetic number, because the mean of its divisors is an integer number (334561).

2⁶⁶⁹¹²¹ is an apocalyptic number.

It is an amenable number.

669121 is a deficient number, since it is larger than the sum of its proper divisors (1).

669121 is an equidigital number, since it uses as much as digits as its factorization.

669121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 648, while the sum is 25.

The square root of 669121 is about 817.9981662571. The cubic root of 669121 is about 87.4651180689.

The spelling of 669121 in words is "six hundred sixty-nine thousand, one hundred twenty-one".