7288021 has 4 divisors (see below), whose sum is σ = 7848652. Its totient is φ = 6727392.

The previous prime is 7288013. The next prime is 7288031. The reversal of 7288021 is 1208827.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2924100 + 4363921 = 1710^2 + 2089^2 .

It is a cyclic number.

It is not a de Polignac number, because 7288021 - 2³ = 7288013 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (7288031) 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, 280296 + ... + 280321.

It is an arithmetic number, because the mean of its divisors is an integer number (1962163).

Almost surely, 2^7288021 is an apocalyptic number.

It is an amenable number.

7288021 is a deficient number, since it is larger than the sum of its proper divisors (560631).

7288021 is a wasteful number, since it uses less digits than its factorization.

7288021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 560630.

The product of its (nonzero) digits is 1792, while the sum is 28.

The square root of 7288021 is about 2699.6334936432. The cubic root of 7288021 is about 193.8815747279.

The spelling of 7288021 in words is "seven million, two hundred eighty-eight thousand, twenty-one".