39986816 has 16 divisors (see below), whose sum is σ = 79661490. Its totient is φ = 19993344.

The previous prime is 39986803. The next prime is 39986819. The reversal of 39986816 is 61868993.

It can be written as a sum of positive squares in only one way, i.e., 32718400 + 7268416 = 5720^2 + 2696^2 .

It is a tau number, because it is divible by the number of its divisors (16).

It is not an unprimeable number, because it can be changed into a prime (39986819) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 156071 + ... + 156326.

Almost surely, 2^39986816 is an apocalyptic number.

It is an amenable number.

39986816 is a deficient number, since it is larger than the sum of its proper divisors (39674674).

39986816 is an equidigital number, since it uses as much as digits as its factorization.

39986816 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 312411 (or 312399 counting only the distinct ones).

The product of its digits is 559872, while the sum is 50.

The square root of 39986816 is about 6323.5129477214. The cubic root of 39986816 is about 341.9576113350.

The spelling of 39986816 in words is "thirty-nine million, nine hundred eighty-six thousand, eight hundred sixteen".