218638097 has 8 divisors (see below), whose sum is σ = 221312616. Its totient is φ = 215972352.

The previous prime is 218638087. The next prime is 218638099. The reversal of 218638097 is 790836812.

It can be written as a sum of positive squares in 4 ways, for example, as 5740816 + 212897281 = 2396^2 + 14591^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 218638097 - 2¹⁴ = 218621713 is a prime.

It is not an unprimeable number, because it can be changed into a prime (218638099) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 57623 + ... + 61299.

It is an arithmetic number, because the mean of its divisors is an integer number (27664077).

Almost surely, 2^218638097 is an apocalyptic number.

It is an amenable number.

218638097 is a deficient number, since it is larger than the sum of its proper divisors (2674519).

218638097 is an equidigital number, since it uses as much as digits as its factorization.

218638097 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4387.

The product of its (nonzero) digits is 145152, while the sum is 44.

The square root of 218638097 is about 14786.4159619564. The cubic root of 218638097 is about 602.4328048430.

The spelling of 218638097 in words is "two hundred eighteen million, six hundred thirty-eight thousand, ninety-seven".