3990000 has 200 divisors, whose sum is σ = 15495040. Its totient is φ = 864000.

The previous prime is 3989989. The next prime is 3990001. The reversal of 3990000 is 993.

It is a tau number, because it is divible by the number of its divisors (200).

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a zygodrome in base 2.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3990001) by changing a digit.

It is a polite number, since it can be written in 39 ways as a sum of consecutive naturals, for example, 209991 + ... + 210009.

Almost surely, 2^3990000 is an apocalyptic number.

3990000 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 3990000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (7747520).

3990000 is an abundant number, since it is smaller than the sum of its proper divisors (11505040).

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

3990000 is a wasteful number, since it uses less digits than its factorization.

3990000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 57 (or 36 counting only the distinct ones).

The product of its (nonzero) digits is 243, while the sum is 21.

The square root of 3990000 is about 1997.4984355438. The cubic root of 3990000 is about 158.6077113863.

Adding to 3990000 its reverse (993), we get a palindrome (3990993).

The spelling of 3990000 in words is "three million, nine hundred ninety thousand".