218933397457 has 2 divisors, whose sum is σ = 218933397458. Its totient is φ = 218933397456.

The previous prime is 218933397443. The next prime is 218933397481. The reversal of 218933397457 is 754793339812.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 199951171281 + 18982226176 = 447159^2 + 137776^2 .

It is a cyclic number.

It is not a de Polignac number, because 218933397457 - 2¹¹ = 218933395409 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 218933397395 and 218933397404.

It is not a weakly prime, because it can be changed into another prime (218933397157) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 109466698728 + 109466698729.

It is an arithmetic number, because the mean of its divisors is an integer number (109466698729).

Almost surely, 2^218933397457 is an apocalyptic number.

It is an amenable number.

218933397457 is a deficient number, since it is larger than the sum of its proper divisors (1).

218933397457 is an equidigital number, since it uses as much as digits as its factorization.

218933397457 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 34292160, while the sum is 61.

The spelling of 218933397457 in words is "two hundred eighteen billion, nine hundred thirty-three million, three hundred ninety-seven thousand, four hundred fifty-seven".