6620440709 has 2 divisors, whose sum is σ = 6620440710. Its totient is φ = 6620440708.

The previous prime is 6620440703. The next prime is 6620440753. The reversal of 6620440709 is 9070440266.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 4460236225 + 2160204484 = 66785^2 + 46478^2 .

It is a cyclic number.

It is not a de Polignac number, because 6620440709 - 2¹⁶ = 6620375173 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (6620440703) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 3310220354 + 3310220355.

It is an arithmetic number, because the mean of its divisors is an integer number (3310220355).

Almost surely, 2^6620440709 is an apocalyptic number.

It is an amenable number.

6620440709 is a deficient number, since it is larger than the sum of its proper divisors (1).

6620440709 is an equidigital number, since it uses as much as digits as its factorization.

6620440709 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 72576, while the sum is 38.

The square root of 6620440709 is about 81366.0906582097. The cubic root of 6620440709 is about 1877.7119354751.

The spelling of 6620440709 in words is "six billion, six hundred twenty million, four hundred forty thousand, seven hundred nine".