57139729 has 4 divisors (see below), whose sum is σ = 58684084. Its totient is φ = 55595376.

The previous prime is 57139699. The next prime is 57139741. The reversal of 57139729 is 92793175.

57139729 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 can be written as a sum of positive squares in 2 ways, for example, as 23232400 + 33907329 = 4820^2 + 5823^2 .

It is a cyclic number.

It is not a de Polignac number, because 57139729 - 2⁵ = 57139697 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (57139769) 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, 772122 + ... + 772195.

It is an arithmetic number, because the mean of its divisors is an integer number (14671021).

Almost surely, 2^57139729 is an apocalyptic number.

It is an amenable number.

57139729 is a deficient number, since it is larger than the sum of its proper divisors (1544355).

57139729 is a wasteful number, since it uses less digits than its factorization.

57139729 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1544354.

The product of its digits is 119070, while the sum is 43.

The square root of 57139729 is about 7559.0825501512. The cubic root of 57139729 is about 385.1643285682.

The spelling of 57139729 in words is "fifty-seven million, one hundred thirty-nine thousand, seven hundred twenty-nine".