251535344240213 has 12 divisors (see below), whose sum is σ = 278927732727084. Its totient is φ = 226644879753600.

The previous prime is 251535344240183. The next prime is 251535344240249. The reversal of 251535344240213 is 312042443535152.

It can be written as a sum of positive squares in 2 ways, for example, as 121595567053444 + 129939777186769 = 11027038^2 + 11399113^2 .

It is not a de Polignac number, because 251535344240213 - 2²⁸ = 251535075804757 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (251535344240273) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 9198236318 + ... + 9198263663.

It is an arithmetic number, because the mean of its divisors is an integer number (23243977727257).

Almost surely, 2^{251535344240213} is an apocalyptic number.

It is an amenable number.

251535344240213 is a deficient number, since it is larger than the sum of its proper divisors (27392388486871).

251535344240213 is a wasteful number, since it uses less digits than its factorization.

251535344240213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18396500116 (or 18396500105 counting only the distinct ones).

The product of its (nonzero) digits is 1728000, while the sum is 44.

Adding to 251535344240213 its reverse (312042443535152), we get a palindrome (563577787775365).

The spelling of 251535344240213 in words is "two hundred fifty-one trillion, five hundred thirty-five billion, three hundred forty-four million, two hundred forty thousand, two hundred thirteen".