3928591421 has 4 divisors (see below), whose sum is σ = 4159685052. Its totient is φ = 3697497792.

The previous prime is 3928591367. The next prime is 3928591427. The reversal of 3928591421 is 1241958293.

3928591421 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2483527225 + 1445064196 = 49835^2 + 38014^2 .

It is a cyclic number.

It is not a de Polignac number, because 3928591421 - 2¹⁰ = 3928590397 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (3928591427) 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, 115546790 + ... + 115546823.

It is an arithmetic number, because the mean of its divisors is an integer number (1039921263).

Almost surely, 2^3928591421 is an apocalyptic number.

It is an amenable number.

3928591421 is a deficient number, since it is larger than the sum of its proper divisors (231093631).

3928591421 is a wasteful number, since it uses less digits than its factorization.

3928591421 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 231093630.

The product of its digits is 155520, while the sum is 44.

The square root of 3928591421 is about 62678.4765370059. The cubic root of 3928591421 is about 1577.8981051576.

The spelling of 3928591421 in words is "three billion, nine hundred twenty-eight million, five hundred ninety-one thousand, four hundred twenty-one".