218587396961 has 2 divisors, whose sum is σ = 218587396962. Its totient is φ = 218587396960.

The previous prime is 218587396921. The next prime is 218587396997. The reversal of 218587396961 is 169693785812.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 128035152400 + 90552244561 = 357820^2 + 300919^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-218587396961 is a prime.

It is a super-2 number, since 2×218587396961² (a number of 23 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (218587396921) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109293698480 + 109293698481.

It is an arithmetic number, because the mean of its divisors is an integer number (109293698481).

Almost surely, 2^218587396961 is an apocalyptic number.

It is an amenable number.

218587396961 is a deficient number, since it is larger than the sum of its proper divisors (1).

218587396961 is an equidigital number, since it uses as much as digits as its factorization.

218587396961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 39191040, while the sum is 65.

The spelling of 218587396961 in words is "two hundred eighteen billion, five hundred eighty-seven million, three hundred ninety-six thousand, nine hundred sixty-one".