3921152221 has 16 divisors (see below), whose sum is σ = 4747970304. Its totient is φ = 3161251584.

The previous prime is 3921152203. The next prime is 3921152239. The reversal of 3921152221 is 1222511293.

3921152221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (3921152203) and next prime (3921152239).

It is a cyclic number.

It is not a de Polignac number, because 3921152221 - 2¹¹ = 3921150173 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 3921152221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3921152021) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 191736 + ... + 211198.

It is an arithmetic number, because the mean of its divisors is an integer number (296748144).

Almost surely, 2^3921152221 is an apocalyptic number.

It is an amenable number.

3921152221 is a deficient number, since it is larger than the sum of its proper divisors (826818083).

3921152221 is a wasteful number, since it uses less digits than its factorization.

3921152221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21180.

The product of its digits is 2160, while the sum is 28.

The square root of 3921152221 is about 62619.1042813613. The cubic root of 3921152221 is about 1576.9015039705.

The spelling of 3921152221 in words is "three billion, nine hundred twenty-one million, one hundred fifty-two thousand, two hundred twenty-one".