55128428 has 6 divisors (see below), whose sum is σ = 96474756. Its totient is φ = 27564212.

The previous prime is 55128421. The next prime is 55128431. The reversal of 55128428 is 82482155.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (55128421) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6891050 + ... + 6891057.

It is an arithmetic number, because the mean of its divisors is an integer number (16079126).

Almost surely, 2^55128428 is an apocalyptic number.

It is an amenable number.

55128428 is a deficient number, since it is larger than the sum of its proper divisors (41346328).

55128428 is a wasteful number, since it uses less digits than its factorization.

55128428 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13782111 (or 13782109 counting only the distinct ones).

The product of its digits is 25600, while the sum is 35.

The square root of 55128428 is about 7424.8520523981. The cubic root of 55128428 is about 380.5910193609.

The spelling of 55128428 in words is "fifty-five million, one hundred twenty-eight thousand, four hundred twenty-eight".