557618021 has 2 divisors, whose sum is σ = 557618022. Its totient is φ = 557618020.

The previous prime is 557617997. The next prime is 557618051. The reversal of 557618021 is 120816755.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 489736900 + 67881121 = 22130^2 + 8239^2 .

It is a cyclic number.

It is not a de Polignac number, because 557618021 - 2¹⁴ = 557601637 is a prime.

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 (557618051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 278809010 + 278809011.

It is an arithmetic number, because the mean of its divisors is an integer number (278809011).

Almost surely, 2^557618021 is an apocalyptic number.

It is an amenable number.

557618021 is a deficient number, since it is larger than the sum of its proper divisors (1).

557618021 is an equidigital number, since it uses as much as digits as its factorization.

557618021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16800, while the sum is 35.

The square root of 557618021 is about 23613.9370076233. The cubic root of 557618021 is about 823.0867305879.

The spelling of 557618021 in words is "five hundred fifty-seven million, six hundred eighteen thousand, twenty-one".