218001531733981 has 2 divisors, whose sum is σ = 218001531733982. Its totient is φ = 218001531733980.

The previous prime is 218001531733969. The next prime is 218001531734023. The reversal of 218001531733981 is 189337135100812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 190100423111481 + 27901108622500 = 13787691^2 + 5282150^2 .

It is a cyclic number.

It is not a de Polignac number, because 218001531733981 - 2²¹ = 218001529636829 is a prime.

It is a super-2 number, since 2×218001531733981² (a number of 29 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218001531733681) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109000765866990 + 109000765866991.

It is an arithmetic number, because the mean of its divisors is an integer number (109000765866991).

Almost surely, 2^{218001531733981} is an apocalyptic number.

It is an amenable number.

218001531733981 is a deficient number, since it is larger than the sum of its proper divisors (1).

218001531733981 is an equidigital number, since it uses as much as digits as its factorization.

218001531733981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1088640, while the sum is 52.

The spelling of 218001531733981 in words is "two hundred eighteen trillion, one billion, five hundred thirty-one million, seven hundred thirty-three thousand, nine hundred eighty-one".