39808640 has 32 divisors (see below), whose sum is σ = 95169060. Its totient is φ = 15923200.

The previous prime is 39808631. The next prime is 39808649. The reversal of 39808640 is 4680893.

39808640 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (39808631) and next prime (39808649).

It can be written as a sum of positive squares in 2 ways, for example, as 35904064 + 3904576 = 5992^2 + 1976^2 .

It is a tau number, because it is divible by the number of its divisors (32).

It is a junction number, because it is equal to n+sod(n) for n = 39808594 and 39808603.

It is not an unprimeable number, because it can be changed into a prime (39808649) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 30461 + ... + 31740.

Almost surely, 2^39808640 is an apocalyptic number.

It is an amenable number.

39808640 is an abundant number, since it is smaller than the sum of its proper divisors (55360420).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

39808640 is an equidigital number, since it uses as much as digits as its factorization.

39808640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 62220 (or 62208 counting only the distinct ones).

The product of its (nonzero) digits is 41472, while the sum is 38.

The square root of 39808640 is about 6309.4088471108. The cubic root of 39808640 is about 341.4489490072.

The spelling of 39808640 in words is "thirty-nine million, eight hundred eight thousand, six hundred forty".