7210421 has 2 divisors, whose sum is σ = 7210422. Its totient is φ = 7210420.

The previous prime is 7210403. The next prime is 7210433. The reversal of 7210421 is 1240127.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 6180196 + 1030225 = 2486^2 + 1015^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7210421 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 7210421.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7210451) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3605210 + 3605211.

It is an arithmetic number, because the mean of its divisors is an integer number (3605211).

Almost surely, 2^7210421 is an apocalyptic number.

It is an amenable number.

7210421 is a deficient number, since it is larger than the sum of its proper divisors (1).

7210421 is an equidigital number, since it uses as much as digits as its factorization.

7210421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 112, while the sum is 17.

The square root of 7210421 is about 2685.2227095718. Note that the first 3 decimals coincide. The cubic root of 7210421 is about 193.1909927974.

Adding to 7210421 its reverse (1240127), we get a palindrome (8450548).

The spelling of 7210421 in words is "seven million, two hundred ten thousand, four hundred twenty-one".