57042809 has 2 divisors, whose sum is σ = 57042810. Its totient is φ = 57042808.

The previous prime is 57042781. The next prime is 57042823. The reversal of 57042809 is 90824075.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 55279225 + 1763584 = 7435^2 + 1328^2 .

It is a cyclic number.

It is not a de Polignac number, because 57042809 - 2¹² = 57038713 is a prime.

It is a super-3 number, since 3×57042809³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a plaindrome in base 16.

It is not a weakly prime, because it can be changed into another prime (57042889) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28521404 + 28521405.

It is an arithmetic number, because the mean of its divisors is an integer number (28521405).

Almost surely, 2^57042809 is an apocalyptic number.

It is an amenable number.

57042809 is a deficient number, since it is larger than the sum of its proper divisors (1).

57042809 is an equidigital number, since it uses as much as digits as its factorization.

57042809 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20160, while the sum is 35.

The square root of 57042809 is about 7552.6689984402. The cubic root of 57042809 is about 384.9464343310.

The spelling of 57042809 in words is "fifty-seven million, forty-two thousand, eight hundred nine".