7218836 has 6 divisors (see below), whose sum is σ = 12632970. Its totient is φ = 3609416.

The previous prime is 7218821. The next prime is 7218839. The reversal of 7218836 is 6388127.

It can be written as a sum of positive squares in only one way, i.e., 6728836 + 490000 = 2594^2 + 700^2 .

It is a super-2 number, since 2×7218836² = 104223186389792, which contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 7218796 and 7218805.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7218839) 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 as a sum of consecutive naturals, namely, 902351 + ... + 902358.

It is an arithmetic number, because the mean of its divisors is an integer number (2105495).

Almost surely, 2^7218836 is an apocalyptic number.

It is an amenable number.

7218836 is a deficient number, since it is larger than the sum of its proper divisors (5414134).

7218836 is a wasteful number, since it uses less digits than its factorization.

7218836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1804713 (or 1804711 counting only the distinct ones).

The product of its digits is 16128, while the sum is 35.

The square root of 7218836 is about 2686.7891618063. The cubic root of 7218836 is about 193.2661187936.

The spelling of 7218836 in words is "seven million, two hundred eighteen thousand, eight hundred thirty-six".