3999020221 has 16 divisors (see below), whose sum is σ = 4751712000. Its totient is φ = 3292869888.

The previous prime is 3999020213. The next prime is 3999020237. The reversal of 3999020221 is 1220209993.

It is not a de Polignac number, because 3999020221 - 2³ = 3999020213 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3999020021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9100 + ... + 89893.

It is an arithmetic number, because the mean of its divisors is an integer number (296982000).

Almost surely, 2^3999020221 is an apocalyptic number.

It is an amenable number.

3999020221 is a deficient number, since it is larger than the sum of its proper divisors (752691779).

3999020221 is a wasteful number, since it uses less digits than its factorization.

3999020221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 99228.

The product of its (nonzero) digits is 17496, while the sum is 37.

The square root of 3999020221 is about 63237.8068958752. The cubic root of 3999020221 is about 1587.2714328665.

The spelling of 3999020221 in words is "three billion, nine hundred ninety-nine million, twenty thousand, two hundred twenty-one".