7218281 has 8 divisors (see below), whose sum is σ = 8441664. Its totient is φ = 6042960.

The previous prime is 7218269. The next prime is 7218311. The reversal of 7218281 is 1828127.

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

It is a de Polignac number, because none of the positive numbers 2^k-7218281 is a prime.

It is a super-2 number, since 2×7218281² = 104207161189922, which contains 22 as substring.

It is an Ulam number.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (7218221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 11690 + ... + 12291.

It is an arithmetic number, because the mean of its divisors is an integer number (1055208).

Almost surely, 2^7218281 is an apocalyptic number.

It is an amenable number.

7218281 is a deficient number, since it is larger than the sum of its proper divisors (1223383).

7218281 is a wasteful number, since it uses less digits than its factorization.

7218281 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24031.

The product of its digits is 1792, while the sum is 29.

The square root of 7218281 is about 2686.6858766890. The cubic root of 7218281 is about 193.2611657585.

The spelling of 7218281 in words is "seven million, two hundred eighteen thousand, two hundred eighty-one".