39957409 has 6 divisors (see below), whose sum is σ = 40199010. Its totient is φ = 39717216.

The previous prime is 39957377. The next prime is 39957413. The reversal of 39957409 is 90475993.

It can be written as a sum of positive squares in only one way, i.e., 31047184 + 8910225 = 5572^2 + 2985^2 .

It is not a de Polignac number, because 39957409 - 2⁵ = 39957377 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (39957439) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 39097 + ... + 40105.

It is an arithmetic number, because the mean of its divisors is an integer number (6699835).

Almost surely, 2^39957409 is an apocalyptic number.

It is an amenable number.

39957409 is a deficient number, since it is larger than the sum of its proper divisors (241601).

39957409 is an equidigital number, since it uses as much as digits as its factorization.

39957409 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1407 (or 1208 counting only the distinct ones).

The product of its (nonzero) digits is 306180, while the sum is 46.

The square root of 39957409 is about 6321.1873093589. The cubic root of 39957409 is about 341.8737635855.

The spelling of 39957409 in words is "thirty-nine million, nine hundred fifty-seven thousand, four hundred nine".