39955609 has 2 divisors, whose sum is σ = 39955610. Its totient is φ = 39955608.

The previous prime is 39955603. The next prime is 39955633. The reversal of 39955609 is 90655993.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 33605209 + 6350400 = 5797^2 + 2520^2 .

It is a cyclic number.

It is not a de Polignac number, because 39955609 - 2¹⁷ = 39824537 is a prime.

It is not a weakly prime, because it can be changed into another prime (39955603) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 19977804 + 19977805.

It is an arithmetic number, because the mean of its divisors is an integer number (19977805).

Almost surely, 2^39955609 is an apocalyptic number.

It is an amenable number.

39955609 is a deficient number, since it is larger than the sum of its proper divisors (1).

39955609 is an equidigital number, since it uses as much as digits as its factorization.

39955609 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 328050, while the sum is 46.

The square root of 39955609 is about 6321.0449294401. The cubic root of 39955609 is about 341.8686299359.

It can be divided in two parts, 3995 and 5609, that added together give a square (9604 = 98²).

The spelling of 39955609 in words is "thirty-nine million, nine hundred fifty-five thousand, six hundred nine".