4028219721 has 8 divisors (see below), whose sum is σ = 5967732960. Its totient is φ = 2685479796.

The previous prime is 4028219693. The next prime is 4028219813. The reversal of 4028219721 is 1279128204.

It is not a de Polignac number, because 4028219721 - 2²³ = 4019831113 is a prime.

It is not an unprimeable number, because it can be changed into a prime (4028219021) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 74596635 + ... + 74596688.

It is an arithmetic number, because the mean of its divisors is an integer number (745966620).

Almost surely, 2^4028219721 is an apocalyptic number.

It is an amenable number.

4028219721 is a deficient number, since it is larger than the sum of its proper divisors (1939513239).

4028219721 is a wasteful number, since it uses less digits than its factorization.

4028219721 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 149193332 (or 149193326 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 36.

The square root of 4028219721 is about 63468.2575859776. The cubic root of 4028219721 is about 1591.1253087601.

The spelling of 4028219721 in words is "four billion, twenty-eight million, two hundred nineteen thousand, seven hundred twenty-one".