218870351881 has 2 divisors, whose sum is σ = 218870351882. Its totient is φ = 218870351880.

The previous prime is 218870351873. The next prime is 218870351989. The reversal of 218870351881 is 188153078812.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 200958544656 + 17911807225 = 448284^2 + 133835^2 .

It is a cyclic number.

It is not a de Polignac number, because 218870351881 - 2³ = 218870351873 is a prime.

It is a super-2 number, since 2×218870351881² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (218870351851) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109435175940 + 109435175941.

It is an arithmetic number, because the mean of its divisors is an integer number (109435175941).

Almost surely, 2^218870351881 is an apocalyptic number.

It is an amenable number.

218870351881 is a deficient number, since it is larger than the sum of its proper divisors (1).

218870351881 is an equidigital number, since it uses as much as digits as its factorization.

218870351881 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 860160, while the sum is 52.

The spelling of 218870351881 in words is "two hundred eighteen billion, eight hundred seventy million, three hundred fifty-one thousand, eight hundred eighty-one".