3990220021 has 12 divisors (see below), whose sum is σ = 4183068960. Its totient is φ = 3805919480.

The previous prime is 3990220019. The next prime is 3990220051. The reversal of 3990220021 is 1200220993.

3990220021 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 3990220021 - 2¹ = 3990220019 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3990220051) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 179406 + ... + 200416.

It is an arithmetic number, because the mean of its divisors is an integer number (348589080).

Almost surely, 2^3990220021 is an apocalyptic number.

It is an amenable number.

3990220021 is a deficient number, since it is larger than the sum of its proper divisors (192848939).

3990220021 is a wasteful number, since it uses less digits than its factorization.

3990220021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21416 (or 21393 counting only the distinct ones).

The product of its (nonzero) digits is 1944, while the sum is 28.

The square root of 3990220021 is about 63168.1883624978. The cubic root of 3990220021 is about 1586.1062670673.

The spelling of 3990220021 in words is "three billion, nine hundred ninety million, two hundred twenty thousand, twenty-one".