213128057257 has 4 divisors (see below), whose sum is σ = 213129162880. Its totient is φ = 213126951636.

The previous prime is 213128057243. The next prime is 213128057269. The reversal of 213128057257 is 752750821312.

213128057257 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, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-213128057257 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (213128057357) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 179733 + ... + 677170.

It is an arithmetic number, because the mean of its divisors is an integer number (53282290720).

Almost surely, 2^213128057257 is an apocalyptic number.

It is an amenable number.

213128057257 is a deficient number, since it is larger than the sum of its proper divisors (1105623).

213128057257 is an equidigital number, since it uses as much as digits as its factorization.

213128057257 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1105622.

The product of its (nonzero) digits is 235200, while the sum is 43.

Adding to 213128057257 its reverse (752750821312), we get a palindrome (965878878569).

The spelling of 213128057257 in words is "two hundred thirteen billion, one hundred twenty-eight million, fifty-seven thousand, two hundred fifty-seven".