123128955 has 24 divisors (see below), whose sum is σ = 217968192. Its totient is φ = 64270464.

The previous prime is 123128947. The next prime is 123128963. The reversal of 123128955 is 559821321.

It is an interprime number because it is at equal distance from previous prime (123128947) and next prime (123128963).

It is not a de Polignac number, because 123128955 - 2³ = 123128947 is a prime.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 26994 + ... + 31223.

It is an arithmetic number, because the mean of its divisors is an integer number (9082008).

Almost surely, 2^123128955 is an apocalyptic number.

123128955 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

123128955 is a deficient number, since it is larger than the sum of its proper divisors (94839237).

123128955 is a wasteful number, since it uses less digits than its factorization.

123128955 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 58275 (or 58272 counting only the distinct ones).

The product of its digits is 21600, while the sum is 36.

The square root of 123128955 is about 11096.3487237920. The cubic root of 123128955 is about 497.4927214578.

The spelling of 123128955 in words is "one hundred twenty-three million, one hundred twenty-eight thousand, nine hundred fifty-five".