55128707 has 4 divisors (see below), whose sum is σ = 55152576. Its totient is φ = 55104840.

The previous prime is 55128679. The next prime is 55128721. The reversal of 55128707 is 70782155.

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

It is a cyclic number.

It is not a de Polignac number, because 55128707 - 2¹⁶ = 55063171 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (55128727) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 8048 + ... + 13229.

It is an arithmetic number, because the mean of its divisors is an integer number (13788144).

Almost surely, 2^55128707 is an apocalyptic number.

55128707 is a deficient number, since it is larger than the sum of its proper divisors (23869).

55128707 is a wasteful number, since it uses less digits than its factorization.

55128707 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 23868.

The product of its (nonzero) digits is 19600, while the sum is 35.

The square root of 55128707 is about 7424.8708406275. The cubic root of 55128707 is about 380.5916614054.

The spelling of 55128707 in words is "fifty-five million, one hundred twenty-eight thousand, seven hundred seven".