39809990 has 16 divisors (see below), whose sum is σ = 78172560. Its totient is φ = 14476320.

The previous prime is 39809989. The next prime is 39809999. The reversal of 39809990 is 9990893.

It is a happy number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39809999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 180845 + ... + 181064.

It is an arithmetic number, because the mean of its divisors is an integer number (4885785).

Almost surely, 2^39809990 is an apocalyptic number.

39809990 is a deficient number, since it is larger than the sum of its proper divisors (38362570).

39809990 is a wasteful number, since it uses less digits than its factorization.

39809990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 361927.

The product of its (nonzero) digits is 157464, while the sum is 47.

The square root of 39809990 is about 6309.5158292852. The cubic root of 39809990 is about 341.4528087294.

The spelling of 39809990 in words is "thirty-nine million, eight hundred nine thousand, nine hundred ninety".