689182121 has 2 divisors, whose sum is σ = 689182122. Its totient is φ = 689182120.

The previous prime is 689182069. The next prime is 689182163. The reversal of 689182121 is 121281986.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 597118096 + 92064025 = 24436^2 + 9595^2 .

It is a cyclic number.

It is not a de Polignac number, because 689182121 - 2¹⁸ = 688919977 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (689182171) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 344591060 + 344591061.

It is an arithmetic number, because the mean of its divisors is an integer number (344591061).

Almost surely, 2^689182121 is an apocalyptic number.

It is an amenable number.

689182121 is a deficient number, since it is larger than the sum of its proper divisors (1).

689182121 is an equidigital number, since it uses as much as digits as its factorization.

689182121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 13824, while the sum is 38.

The square root of 689182121 is about 26252.2783963602. The cubic root of 689182121 is about 883.3063124838.

The spelling of 689182121 in words is "six hundred eighty-nine million, one hundred eighty-two thousand, one hundred twenty-one".