39990240 has 96 divisors (see below), whose sum is σ = 139980960. Its totient is φ = 10662912.

The previous prime is 39990233. The next prime is 39990241. The reversal of 39990240 is 4209993.

It is a tau number, because it is divible by the number of its divisors (96).

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a junction number, because it is equal to n+sod(n) for n = 39990195 and 39990204.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (39990241) by changing a digit.

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 15 ways as a sum of consecutive naturals, for example, 309 + ... + 8948.

It is an arithmetic number, because the mean of its divisors is an integer number (1458135).

Almost surely, 2^39990240 is an apocalyptic number.

39990240 is a gapful number since it is divisible by the number (30) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 39990240, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (69990480).

39990240 is an abundant number, since it is smaller than the sum of its proper divisors (99990720).

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

39990240 is a wasteful number, since it uses less digits than its factorization.

39990240 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9281 (or 9267 counting only the distinct ones).

The product of its (nonzero) digits is 17496, while the sum is 36.

The square root of 39990240 is about 6323.7836775146. The cubic root of 39990240 is about 341.9673714640.

The spelling of 39990240 in words is "thirty-nine million, nine hundred ninety thousand, two hundred forty".