7318021 has 4 divisors (see below), whose sum is σ = 7703200. Its totient is φ = 6932844.

The previous prime is 7318019. The next prime is 7318033. The reversal of 7318021 is 1208137.

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 a cyclic number.

It is not a de Polignac number, because 7318021 - 2¹ = 7318019 is a prime.

It is a Duffinian number.

7318021 is a lucky number.

It is a junction number, because it is equal to n+sod(n) for n = 7317983 and 7318001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7318061) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 192561 + ... + 192598.

It is an arithmetic number, because the mean of its divisors is an integer number (1925800).

Almost surely, 2^7318021 is an apocalyptic number.

It is an amenable number.

7318021 is a deficient number, since it is larger than the sum of its proper divisors (385179).

7318021 is a wasteful number, since it uses less digits than its factorization.

7318021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 385178.

The product of its (nonzero) digits is 336, while the sum is 22.

The square root of 7318021 is about 2705.1840972474. The cubic root of 7318021 is about 194.1472382786.

The spelling of 7318021 in words is "seven million, three hundred eighteen thousand, twenty-one".