57721947 has 4 divisors (see below), whose sum is σ = 76962600. Its totient is φ = 38481296.

The previous prime is 57721933. The next prime is 57721949. The reversal of 57721947 is 74912775.

57721947 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.

It is a cyclic number.

It is not a de Polignac number, because 57721947 - 2⁸ = 57721691 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 57721899 and 57721908.

It is not an unprimeable number, because it can be changed into a prime (57721949) 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, 9620322 + ... + 9620327.

It is an arithmetic number, because the mean of its divisors is an integer number (19240650).

Almost surely, 2^57721947 is an apocalyptic number.

57721947 is a deficient number, since it is larger than the sum of its proper divisors (19240653).

57721947 is a wasteful number, since it uses less digits than its factorization.

57721947 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19240652.

The product of its digits is 123480, while the sum is 42.

The square root of 57721947 is about 7597.4961006900. The cubic root of 57721947 is about 386.4681046342.

The spelling of 57721947 in words is "fifty-seven million, seven hundred twenty-one thousand, nine hundred forty-seven".