128296665 has 24 divisors (see below), whose sum is σ = 254150208. Its totient is φ = 58649760.

The previous prime is 128296661. The next prime is 128296681. The reversal of 128296665 is 566692821.

It is not a de Polignac number, because 128296665 - 2² = 128296661 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 128296665.

It is not an unprimeable number, because it can be changed into a prime (128296661) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 203331 + ... + 203960.

It is an arithmetic number, because the mean of its divisors is an integer number (10589592).

Almost surely, 2^128296665 is an apocalyptic number.

128296665 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

128296665 is a deficient number, since it is larger than the sum of its proper divisors (125853543).

128296665 is a wasteful number, since it uses less digits than its factorization.

128296665 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 407309 (or 407306 counting only the distinct ones).

The product of its digits is 311040, while the sum is 45.

The square root of 128296665 is about 11326.8117756057. The cubic root of 128296665 is about 504.3574679625.

The spelling of 128296665 in words is "one hundred twenty-eight million, two hundred ninety-six thousand, six hundred sixty-five".