128889601 has 4 divisors (see below), whose sum is σ = 133334100. Its totient is φ = 124445104.

The previous prime is 128889589. The next prime is 128889617. The reversal of 128889601 is 106988821.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 29986576 + 98903025 = 5476^2 + 9945^2 .

It is a cyclic number.

It is not a de Polignac number, because 128889601 - 2⁷ = 128889473 is a prime.

It is a super-2 number, since 2×128889601² = 33225058491878402, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128889641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2222206 + ... + 2222263.

It is an arithmetic number, because the mean of its divisors is an integer number (33333525).

Almost surely, 2^128889601 is an apocalyptic number.

It is an amenable number.

128889601 is a deficient number, since it is larger than the sum of its proper divisors (4444499).

128889601 is an equidigital number, since it uses as much as digits as its factorization.

128889601 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4444498.

The product of its (nonzero) digits is 55296, while the sum is 43.

The square root of 128889601 is about 11352.9556063608. The cubic root of 128889601 is about 505.1332537287.

The spelling of 128889601 in words is "one hundred twenty-eight million, eight hundred eighty-nine thousand, six hundred one".