128892889 has 4 divisors (see below), whose sum is σ = 132036660. Its totient is φ = 125749120.

The previous prime is 128892877. The next prime is 128892923. The reversal of 128892889 is 988298821.

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 33732864 + 95160025 = 5808^2 + 9755^2 .

It is a cyclic number.

It is not a de Polignac number, because 128892889 - 2⁵ = 128892857 is a prime.

It is a super-2 number, since 2×128892889² = 33226753669532642, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128892839) 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, 1571824 + ... + 1571905.

It is an arithmetic number, because the mean of its divisors is an integer number (33009165).

Almost surely, 2^128892889 is an apocalyptic number.

It is an amenable number.

128892889 is a deficient number, since it is larger than the sum of its proper divisors (3143771).

128892889 is an equidigital number, since it uses as much as digits as its factorization.

128892889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3143770.

The product of its digits is 1327104, while the sum is 55.

The square root of 128892889 is about 11353.1004135434. The cubic root of 128892889 is about 505.1375490429.

The spelling of 128892889 in words is "one hundred twenty-eight million, eight hundred ninety-two thousand, eight hundred eighty-nine".