3990021012 has 96 divisors (see below), whose sum is σ = 10501142400. Its totient is φ = 1310017536.

The previous prime is 3990021001. The next prime is 3990021019. The reversal of 3990021012 is 2101200993.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3990021019) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 2229414 + ... + 2231202.

It is an arithmetic number, because the mean of its divisors is an integer number (109386900).

Almost surely, 2^3990021012 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 3990021012, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (5250571200).

3990021012 is an abundant number, since it is smaller than the sum of its proper divisors (6511121388).

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

3990021012 is a wasteful number, since it uses less digits than its factorization.

3990021012 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2102 (or 2094 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 27.

The square root of 3990021012 is about 63166.6131116747. The cubic root of 3990021012 is about 1586.0798980394.

The spelling of 3990021012 in words is "three billion, nine hundred ninety million, twenty-one thousand, twelve".