7218981 has 36 divisors (see below), whose sum is σ = 13112736. Its totient is φ = 3746160.

The previous prime is 7218979. The next prime is 7218983. The reversal of 7218981 is 1898127.

7218981 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (7218979) and next prime (7218983).

It is not a de Polignac number, because 7218981 - 2¹ = 7218979 is a prime.

It is a super-2 number, since 2×7218981² = 104227373356722, which contains 22 as substring.

It is an alternating number because its digits alternate between odd and even.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7218983) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 7150 + ... + 8096.

Almost surely, 2^7218981 is an apocalyptic number.

It is an amenable number.

7218981 is a deficient number, since it is larger than the sum of its proper divisors (5893755).

7218981 is a wasteful number, since it uses less digits than its factorization.

7218981 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 982 (or 968 counting only the distinct ones).

The product of its digits is 8064, while the sum is 36.

The square root of 7218981 is about 2686.8161455522. The cubic root of 7218981 is about 193.2674127880.

The spelling of 7218981 in words is "seven million, two hundred eighteen thousand, nine hundred eighty-one".