8722409 has 2 divisors, whose sum is σ = 8722410. Its totient is φ = 8722408.

The previous prime is 8722393. The next prime is 8722423. The reversal of 8722409 is 9042278.

8722409 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 7728400 + 994009 = 2780^2 + 997^2 .

It is a cyclic number.

It is not a de Polignac number, because 8722409 - 2⁴ = 8722393 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (8722429) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 4361204 + 4361205.

It is an arithmetic number, because the mean of its divisors is an integer number (4361205).

Almost surely, 2^8722409 is an apocalyptic number.

It is an amenable number.

8722409 is a deficient number, since it is larger than the sum of its proper divisors (1).

8722409 is an equidigital number, since it uses as much as digits as its factorization.

8722409 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8064, while the sum is 32.

The square root of 8722409 is about 2953.3724790483. The cubic root of 8722409 is about 205.8474457297.

The spelling of 8722409 in words is "eight million, seven hundred twenty-two thousand, four hundred nine".