55728649 has 4 divisors (see below), whose sum is σ = 55749780. Its totient is φ = 55707520.

The previous prime is 55728641. The next prime is 55728667. The reversal of 55728649 is 94682755.

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

It can be written as a sum of positive squares in 2 ways, for example, as 25401600 + 30327049 = 5040^2 + 5507^2 .

It is a cyclic number.

It is not a de Polignac number, because 55728649 - 2³ = 55728641 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 55728599 and 55728608.

It is not an unprimeable number, because it can be changed into a prime (55728641) 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, 5932 + ... + 12109.

It is an arithmetic number, because the mean of its divisors is an integer number (13937445).

Almost surely, 2^55728649 is an apocalyptic number.

It is an amenable number.

55728649 is a deficient number, since it is larger than the sum of its proper divisors (21131).

55728649 is a wasteful number, since it uses less digits than its factorization.

55728649 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21130.

The product of its digits is 604800, while the sum is 46.

The square root of 55728649 is about 7465.1623559036. The cubic root of 55728649 is about 381.9672883916.

The spelling of 55728649 in words is "fifty-five million, seven hundred twenty-eight thousand, six hundred forty-nine".