57206381 has 2 divisors, whose sum is σ = 57206382. Its totient is φ = 57206380.

The previous prime is 57206371. The next prime is 57206407. The reversal of 57206381 is 18360275.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 40322500 + 16883881 = 6350^2 + 4109^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-57206381 is a prime.

It is a super-3 number, since 3×57206381³ (a number of 24 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (57206311) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 28603190 + 28603191.

It is an arithmetic number, because the mean of its divisors is an integer number (28603191).

Almost surely, 2^57206381 is an apocalyptic number.

It is an amenable number.

57206381 is a deficient number, since it is larger than the sum of its proper divisors (1).

57206381 is an equidigital number, since it uses as much as digits as its factorization.

57206381 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 57206381 is about 7563.4900013155. The cubic root of 57206381 is about 385.3140317482.

The spelling of 57206381 in words is "fifty-seven million, two hundred six thousand, three hundred eighty-one".