218851437653 has 2 divisors, whose sum is σ = 218851437654. Its totient is φ = 218851437652.

The previous prime is 218851437533. The next prime is 218851437683. The reversal of 218851437653 is 356734158812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 214107947524 + 4743490129 = 462718^2 + 68873^2 .

It is a cyclic number.

It is not a de Polignac number, because 218851437653 - 2²⁴ = 218834660437 is a prime.

It is a super-2 number, since 2×218851437653² (a number of 23 digits) contains 22 as substring.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 218851437595 and 218851437604.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (218851437683) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109425718826 + 109425718827.

It is an arithmetic number, because the mean of its divisors is an integer number (109425718827).

Almost surely, 2^218851437653 is an apocalyptic number.

It is an amenable number.

218851437653 is a deficient number, since it is larger than the sum of its proper divisors (1).

218851437653 is an equidigital number, since it uses as much as digits as its factorization.

218851437653 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4838400, while the sum is 53.

The spelling of 218851437653 in words is "two hundred eighteen billion, eight hundred fifty-one million, four hundred thirty-seven thousand, six hundred fifty-three".