128105569 has 2 divisors, whose sum is σ = 128105570. Its totient is φ = 128105568.

The previous prime is 128105539. The next prime is 128105573. The reversal of 128105569 is 965501821.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 111197025 + 16908544 = 10545^2 + 4112^2 .

It is an emirp because it is prime and its reverse (965501821) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 128105569 - 2²¹ = 126008417 is a prime.

It is a super-2 number, since 2×128105569² = 32822073617627522, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (128105519) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 64052784 + 64052785.

It is an arithmetic number, because the mean of its divisors is an integer number (64052785).

Almost surely, 2^128105569 is an apocalyptic number.

It is an amenable number.

128105569 is a deficient number, since it is larger than the sum of its proper divisors (1).

128105569 is an equidigital number, since it uses as much as digits as its factorization.

128105569 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 21600, while the sum is 37.

The square root of 128105569 is about 11318.3730721336. The cubic root of 128105569 is about 504.1069325157.

The spelling of 128105569 in words is "one hundred twenty-eight million, one hundred five thousand, five hundred sixty-nine".