39999920 has 60 divisors (see below), whose sum is σ = 96761664. Its totient is φ = 15361920.

The previous prime is 39999919. The next prime is 39999931. The reversal of 39999920 is 2999993.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 314897 + ... + 315023.

Almost surely, 2^39999920 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 39999920, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48380832).

39999920 is an abundant number, since it is smaller than the sum of its proper divisors (56761744).

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

39999920 is a wasteful number, since it uses less digits than its factorization.

39999920 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 298 (or 165 counting only the distinct ones).

The product of its (nonzero) digits is 354294, while the sum is 50.

The square root of 39999920 is about 6324.5489957783. The cubic root of 39999920 is about 341.9949613384.

The spelling of 39999920 in words is "thirty-nine million, nine hundred ninety-nine thousand, nine hundred twenty".