213131257 has 2 divisors, whose sum is σ = 213131258. Its totient is φ = 213131256.

The previous prime is 213131249. The next prime is 213131291. The reversal of 213131257 is 752131312.

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., 212314041 + 817216 = 14571^2 + 904^2 .

It is a cyclic number.

It is not a de Polignac number, because 213131257 - 2³ = 213131249 is a prime.

It is not a weakly prime, because it can be changed into another prime (213131207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106565628 + 106565629.

It is an arithmetic number, because the mean of its divisors is an integer number (106565629).

Almost surely, 2^213131257 is an apocalyptic number.

It is an amenable number.

213131257 is a deficient number, since it is larger than the sum of its proper divisors (1).

213131257 is an equidigital number, since it uses as much as digits as its factorization.

213131257 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1260, while the sum is 25.

The square root of 213131257 is about 14599.0156174997. The cubic root of 213131257 is about 597.3319095569.

Adding to 213131257 its reverse (752131312), we get a palindrome (965262569).

The spelling of 213131257 in words is "two hundred thirteen million, one hundred thirty-one thousand, two hundred fifty-seven".