7021381 has 2 divisors, whose sum is σ = 7021382. Its totient is φ = 7021380.

The previous prime is 7021367. The next prime is 7021423. The reversal of 7021381 is 1831207.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4990756 + 2030625 = 2234^2 + 1425^2 .

It is a cyclic number.

It is not a de Polignac number, because 7021381 - 2⁷ = 7021253 is a prime.

It is a super-3 number, since 3×7021381³ (a number of 22 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is a Chen prime.

It is an Ulam number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (7021321) 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, 3510690 + 3510691.

It is an arithmetic number, because the mean of its divisors is an integer number (3510691).

Almost surely, 2^7021381 is an apocalyptic number.

It is an amenable number.

7021381 is a deficient number, since it is larger than the sum of its proper divisors (1).

7021381 is an equidigital number, since it uses as much as digits as its factorization.

7021381 is an odious number, because the sum of its binary digits is odd.

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

The square root of 7021381 is about 2649.7888595131. The cubic root of 7021381 is about 191.4876840377.

Adding to 7021381 its reverse (1831207), we get a palindrome (8852588).

The spelling of 7021381 in words is "seven million, twenty-one thousand, three hundred eighty-one".