3921134221 has 4 divisors (see below), whose sum is σ = 3924722812. Its totient is φ = 3917545632.

The previous prime is 3921134219. The next prime is 3921134227. The reversal of 3921134221 is 1224311293.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1224311293 = 1699 ⋅720607.

It can be written as a sum of positive squares in 2 ways, for example, as 3768240996 + 152893225 = 61386^2 + 12365^2 .

It is a cyclic number.

It is not a de Polignac number, because 3921134221 - 2¹ = 3921134219 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 3921134221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3921134227) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1792656 + ... + 1794841.

It is an arithmetic number, because the mean of its divisors is an integer number (981180703).

Almost surely, 2^3921134221 is an apocalyptic number.

It is an amenable number.

3921134221 is a deficient number, since it is larger than the sum of its proper divisors (3588591).

3921134221 is a wasteful number, since it uses less digits than its factorization.

3921134221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3588590.

The product of its digits is 2592, while the sum is 28.

The square root of 3921134221 is about 62618.9605550907. The cubic root of 3921134221 is about 1576.8990910513.

The spelling of 3921134221 in words is "three billion, nine hundred twenty-one million, one hundred thirty-four thousand, two hundred twenty-one".