7187281 has 2 divisors, whose sum is σ = 7187282. Its totient is φ = 7187280.

The previous prime is 7187269. The next prime is 7187317. The reversal of 7187281 is 1827817.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4494400 + 2692881 = 2120^2 + 1641^2 .

It is an emirp because it is prime and its reverse (1827817) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 7187281 - 2⁷ = 7187153 is a prime.

It is a super-2 number, since 2×7187281² = 103314016345922, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (7187221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3593640 + 3593641.

It is an arithmetic number, because the mean of its divisors is an integer number (3593641).

Almost surely, 2^7187281 is an apocalyptic number.

It is an amenable number.

7187281 is a deficient number, since it is larger than the sum of its proper divisors (1).

7187281 is an equidigital number, since it uses as much as digits as its factorization.

7187281 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 6272, while the sum is 34.

The square root of 7187281 is about 2680.9104796692. The cubic root of 7187281 is about 192.9841056470.

The spelling of 7187281 in words is "seven million, one hundred eighty-seven thousand, two hundred eighty-one".