7218971 has 4 divisors (see below), whose sum is σ = 7355232. Its totient is φ = 7082712.

The previous prime is 7218947. The next prime is 7218973. The reversal of 7218971 is 1798127.

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

It is a cyclic number.

It is not a de Polignac number, because 7218971 - 2⁶ = 7218907 is a prime.

It is a super-2 number, since 2×7218971² = 104227084597682, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (7218973) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 68051 + ... + 68156.

It is an arithmetic number, because the mean of its divisors is an integer number (1838808).

Almost surely, 2^7218971 is an apocalyptic number.

7218971 is a deficient number, since it is larger than the sum of its proper divisors (136261).

7218971 is a wasteful number, since it uses less digits than its factorization.

7218971 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 136260.

The product of its digits is 7056, while the sum is 35.

The square root of 7218971 is about 2686.8142846129. The cubic root of 7218971 is about 193.2673235476.

The spelling of 7218971 in words is "seven million, two hundred eighteen thousand, nine hundred seventy-one".