218396869 has 4 divisors (see below), whose sum is σ = 220400620. Its totient is φ = 216393120.

The previous prime is 218396839. The next prime is 218396881. The reversal of 218396869 is 968693812.

It is a happy number.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 85340644 + 133056225 = 9238^2 + 11535^2 .

It is a cyclic number.

It is not a de Polignac number, because 218396869 - 2⁷ = 218396741 is a prime.

It is a super-2 number, since 2×218396869² = 95394384778006322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (218396809) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1001712 + ... + 1001929.

It is an arithmetic number, because the mean of its divisors is an integer number (55100155).

Almost surely, 2^218396869 is an apocalyptic number.

It is an amenable number.

218396869 is a deficient number, since it is larger than the sum of its proper divisors (2003751).

218396869 is a wasteful number, since it uses less digits than its factorization.

218396869 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2003750.

The product of its digits is 1119744, while the sum is 52.

The square root of 218396869 is about 14778.2566292510. The cubic root of 218396869 is about 602.2111643914.

The spelling of 218396869 in words is "two hundred eighteen million, three hundred ninety-six thousand, eight hundred sixty-nine".