4091391639 has 48 divisors (see below), whose sum is σ = 6293064960. Its totient is φ = 2555879040.

The previous prime is 4091391613. The next prime is 4091391641. The reversal of 4091391639 is 9361931904.

4091391639 is a `hidden beast` number, since 4 + 0 + 9 + 1 + 3 + 9 + 1 + 639 = 666.

It is not a de Polignac number, because 4091391639 - 2⁷ = 4091391511 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 4091391594 and 4091391603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4091391679) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 6362652 + ... + 6363294.

It is an arithmetic number, because the mean of its divisors is an integer number (131105520).

Almost surely, 2^4091391639 is an apocalyptic number.

4091391639 is a deficient number, since it is larger than the sum of its proper divisors (2201673321).

4091391639 is a wasteful number, since it uses less digits than its factorization.

With its successor (4091391640) it forms a Ruth-Aaron pair, since the sum of their distinct prime factors is the same (1249).

With its successor (4091391640) it forms an eRAP, since the sums of their prime factors are consecutive (1252 and 1253).

4091391639 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1252 (or 1249 counting only the distinct ones).

The product of its (nonzero) digits is 157464, while the sum is 45.

The square root of 4091391639 is about 63963.9870474004. The cubic root of 4091391639 is about 1599.3997278188.

The spelling of 4091391639 in words is "four billion, ninety-one million, three hundred ninety-one thousand, six hundred thirty-nine".