39981600 has 180 divisors, whose sum is σ = 146041434. Its totient is φ = 10644480.

The previous prime is 39981587. The next prime is 39981607. The reversal of 39981600 is 618993.

It can be written as a sum of positive squares in 3 ways, for example, as 17740944 + 22240656 = 4212^2 + 4716^2 .

It is a tau number, because it is divible by the number of its divisors (180).

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

It is not an unprimeable number, because it can be changed into a prime (39981607) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 29 ways as a sum of consecutive naturals, for example, 64492 + ... + 65108.

Almost surely, 2^39981600 is an apocalyptic number.

39981600 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 39981600, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (73020717).

39981600 is an abundant number, since it is smaller than the sum of its proper divisors (106059834).

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

39981600 is a wasteful number, since it uses less digits than its factorization.

39981600 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 649 (or 627 counting only the distinct ones).

The product of its (nonzero) digits is 11664, while the sum is 36.

The square root of 39981600 is about 6323.1005052901. The cubic root of 39981600 is about 341.9427420302.

The spelling of 39981600 in words is "thirty-nine million, nine hundred eighty-one thousand, six hundred".