30557 has 2 divisors, whose sum is σ = 30558. Its totient is φ = 30556.

The previous prime is 30553. The next prime is 30559. The reversal of 30557 is 75503.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19321 + 11236 = 139^2 + 106^2 .

It is an emirp because it is prime and its reverse (75503) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 30557 - 2² = 30553 is a prime.

Together with 30559, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (30553) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 15278 + 15279.

It is an arithmetic number, because the mean of its divisors is an integer number (15279).

2³⁰⁵⁵⁷ is an apocalyptic number.

It is an amenable number.

30557 is a deficient number, since it is larger than the sum of its proper divisors (1).

30557 is an equidigital number, since it uses as much as digits as its factorization.

30557 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 525, while the sum is 20.

The square root of 30557 is about 174.8056063174. The cubic root of 30557 is about 31.2634502101.

The spelling of 30557 in words is "thirty thousand, five hundred fifty-seven".