128969557 has 2 divisors, whose sum is σ = 128969558. Its totient is φ = 128969556.

The previous prime is 128969527. The next prime is 128969567. The reversal of 128969557 is 755969821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 73034116 + 55935441 = 8546^2 + 7479^2 .

It is a cyclic number.

It is not a de Polignac number, because 128969557 - 2¹⁹ = 128445269 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (128969507) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64484778 + 64484779.

It is an arithmetic number, because the mean of its divisors is an integer number (64484779).

Almost surely, 2^128969557 is an apocalyptic number.

It is an amenable number.

128969557 is a deficient number, since it is larger than the sum of its proper divisors (1).

128969557 is an equidigital number, since it uses as much as digits as its factorization.

128969557 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1360800, while the sum is 52.

The square root of 128969557 is about 11356.4764341762. The cubic root of 128969557 is about 505.2376844079.

The spelling of 128969557 in words is "one hundred twenty-eight million, nine hundred sixty-nine thousand, five hundred fifty-seven".