7142809 has 2 divisors, whose sum is σ = 7142810. Its totient is φ = 7142808.

The previous prime is 7142791. The next prime is 7142819. The reversal of 7142809 is 9082417.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 4347225 + 2795584 = 2085^2 + 1672^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7142809 is a prime.

It is not a weakly prime, because it can be changed into another prime (7142819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3571404 + 3571405.

It is an arithmetic number, because the mean of its divisors is an integer number (3571405).

Almost surely, 2^7142809 is an apocalyptic number.

It is an amenable number.

7142809 is a deficient number, since it is larger than the sum of its proper divisors (1).

7142809 is an equidigital number, since it uses as much as digits as its factorization.

7142809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 4032, while the sum is 31.

The square root of 7142809 is about 2672.6034124052. The cubic root of 7142809 is about 192.5852458786.

The spelling of 7142809 in words is "seven million, one hundred forty-two thousand, eight hundred nine".