4327991 has 4 divisors (see below), whose sum is σ = 4555800. Its totient is φ = 4100184.

The previous prime is 4327963. The next prime is 4328017. The reversal of 4327991 is 1997234.

Added to its reverse (1997234) it gives a square (6325225 = 2515²).

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1997234 = 2 ⋅998617.

It is a cyclic number.

It is not a de Polignac number, because 4327991 - 2¹⁴ = 4311607 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4326991) 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, 113876 + ... + 113913.

It is an arithmetic number, because the mean of its divisors is an integer number (1138950).

Almost surely, 2^4327991 is an apocalyptic number.

4327991 is a deficient number, since it is larger than the sum of its proper divisors (227809).

4327991 is a wasteful number, since it uses less digits than its factorization.

4327991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 227808.

The product of its digits is 13608, while the sum is 35.

The square root of 4327991 is about 2080.3824167686. The cubic root of 4327991 is about 162.9654160258.

Adding to 4327991 its reverse (1997234), we get a square (6325225 = 2515²).

The spelling of 4327991 in words is "four million, three hundred twenty-seven thousand, nine hundred ninety-one".