39990645 has 48 divisors (see below), whose sum is σ = 73634880. Its totient is φ = 20581344.

The previous prime is 39990607. The next prime is 39990653. The reversal of 39990645 is 54609993.

It is a happy number.

39990645 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 39990645 - 2⁸ = 39990389 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (45).

It is a self number, because there is not a number n which added to its sum of digits gives 39990645.

It is a congruent number.

It is an unprimeable number.

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 47 ways as a sum of consecutive naturals, for example, 481774 + ... + 481856.

It is an arithmetic number, because the mean of its divisors is an integer number (1534060).

Almost surely, 2^39990645 is an apocalyptic number.

It is an amenable number.

39990645 is a deficient number, since it is larger than the sum of its proper divisors (33644235).

39990645 is an equidigital number, since it uses as much as digits as its factorization.

39990645 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 223 (or 134 counting only the distinct ones).

The product of its (nonzero) digits is 262440, while the sum is 45.

The square root of 39990645 is about 6323.8156994017. The cubic root of 39990645 is about 341.9685258816.

The spelling of 39990645 in words is "thirty-nine million, nine hundred ninety thousand, six hundred forty-five".