17128121 has 2 divisors, whose sum is σ = 17128122. Its totient is φ = 17128120.

The previous prime is 17128117. The next prime is 17128127. The reversal of 17128121 is 12182171.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 16687225 + 440896 = 4085^2 + 664^2 .

It is a cyclic number.

It is not a de Polignac number, because 17128121 - 2² = 17128117 is a prime.

It is a Chen prime.

It is equal to p_1099031 and since 17128121 and 1099031 have the same sum of digits, it is a Honaker prime.

It is not a weakly prime, because it can be changed into another prime (17128127) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8564060 + 8564061.

It is an arithmetic number, because the mean of its divisors is an integer number (8564061).

Almost surely, 2^17128121 is an apocalyptic number.

It is an amenable number.

17128121 is a deficient number, since it is larger than the sum of its proper divisors (1).

17128121 is an equidigital number, since it uses as much as digits as its factorization.

17128121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 224, while the sum is 23.

The square root of 17128121 is about 4138.6134151428. The cubic root of 17128121 is about 257.7724943937.

The spelling of 17128121 in words is "seventeen million, one hundred twenty-eight thousand, one hundred twenty-one".