218131031513 has 2 divisors, whose sum is σ = 218131031514. Its totient is φ = 218131031512.

The previous prime is 218131031509. The next prime is 218131031551. The reversal of 218131031513 is 315130131812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 192955497289 + 25175534224 = 439267^2 + 158668^2 .

It is a cyclic number.

It is not a de Polignac number, because 218131031513 - 2² = 218131031509 is a prime.

It is a super-2 number, since 2×218131031513² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (218131031593) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109065515756 + 109065515757.

It is an arithmetic number, because the mean of its divisors is an integer number (109065515757).

Almost surely, 2^218131031513 is an apocalyptic number.

It is an amenable number.

218131031513 is a deficient number, since it is larger than the sum of its proper divisors (1).

218131031513 is an equidigital number, since it uses as much as digits as its factorization.

218131031513 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2160, while the sum is 29.

The spelling of 218131031513 in words is "two hundred eighteen billion, one hundred thirty-one million, thirty-one thousand, five hundred thirteen".