72218361 has 4 divisors (see below), whose sum is σ = 96291152. Its totient is φ = 48145572.

The previous prime is 72218353. The next prime is 72218369. The reversal of 72218361 is 16381227.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is an interprime number because it is at equal distance from previous prime (72218353) and next prime (72218369).

It is not a de Polignac number, because 72218361 - 2³ = 72218353 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (72218369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12036391 + ... + 12036396.

It is an arithmetic number, because the mean of its divisors is an integer number (24072788).

Almost surely, 2^72218361 is an apocalyptic number.

It is an amenable number.

72218361 is a deficient number, since it is larger than the sum of its proper divisors (24072791).

72218361 is a wasteful number, since it uses less digits than its factorization.

72218361 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24072790.

The product of its digits is 4032, while the sum is 30.

The square root of 72218361 is about 8498.1386785578. The cubic root of 72218361 is about 416.4369042232.

Adding to 72218361 its reverse (16381227), we get a palindrome (88599588).

The spelling of 72218361 in words is "seventy-two million, two hundred eighteen thousand, three hundred sixty-one".