128887811 has 8 divisors (see below), whose sum is σ = 146107920. Its totient is φ = 112711392.

The previous prime is 128887799. The next prime is 128887859. The reversal of 128887811 is 118788821.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 128887811 - 2¹⁴ = 128871427 is a prime.

It is a super-2 number, since 2×128887811² = 33224135648743442, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (128887111) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 260660 + ... + 261153.

It is an arithmetic number, because the mean of its divisors is an integer number (18263490).

Almost surely, 2^128887811 is an apocalyptic number.

128887811 is a deficient number, since it is larger than the sum of its proper divisors (17220109).

128887811 is a wasteful number, since it uses less digits than its factorization.

128887811 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 521845.

The product of its digits is 57344, while the sum is 44.

The square root of 128887811 is about 11352.8767719904. The cubic root of 128887811 is about 505.1309153122.

The spelling of 128887811 in words is "one hundred twenty-eight million, eight hundred eighty-seven thousand, eight hundred eleven".