50556721 has 4 divisors (see below), whose sum is σ = 50641444. Its totient is φ = 50472000.

The previous prime is 50556713. The next prime is 50556749. The reversal of 50556721 is 12765505.

50556721 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 12765505 = 5 ⋅2553101.

It can be written as a sum of positive squares in 2 ways, for example, as 18792225 + 31764496 = 4335^2 + 5636^2 .

It is a cyclic number.

It is not a de Polignac number, because 50556721 - 2³ = 50556713 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (50556791) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 41460 + ... + 42661.

It is an arithmetic number, because the mean of its divisors is an integer number (12660361).

Almost surely, 2^50556721 is an apocalyptic number.

It is an amenable number.

50556721 is a deficient number, since it is larger than the sum of its proper divisors (84723).

50556721 is an equidigital number, since it uses as much as digits as its factorization.

50556721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 84722.

The product of its (nonzero) digits is 10500, while the sum is 31.

The square root of 50556721 is about 7110.3249574123. The cubic root of 50556721 is about 369.7654247249.

The spelling of 50556721 in words is "fifty million, five hundred fifty-six thousand, seven hundred twenty-one".