128292121 has 2 divisors, whose sum is σ = 128292122. Its totient is φ = 128292120.

The previous prime is 128292097. The next prime is 128292133. The reversal of 128292121 is 121292821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 92160000 + 36132121 = 9600^2 + 6011^2 .

It is a cyclic number.

It is not a de Polignac number, because 128292121 - 2¹¹ = 128290073 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 128292121.

It is not a weakly prime, because it can be changed into another prime (128292181) by changing a digit.

It is a good prime.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64146060 + 64146061.

It is an arithmetic number, because the mean of its divisors is an integer number (64146061).

Almost surely, 2^128292121 is an apocalyptic number.

It is an amenable number.

128292121 is a deficient number, since it is larger than the sum of its proper divisors (1).

128292121 is an equidigital number, since it uses as much as digits as its factorization.

128292121 is an evil number, because the sum of its binary digits is even.

The product of its digits is 1152, while the sum is 28.

The square root of 128292121 is about 11326.6111878178. The cubic root of 128292121 is about 504.3515134627.

The spelling of 128292121 in words is "one hundred twenty-eight million, two hundred ninety-two thousand, one hundred twenty-one".