4127991 has 32 divisors (see below), whose sum is σ = 6893568. Its totient is φ = 2142720.

The previous prime is 4127989. The next prime is 4127993. The reversal of 4127991 is 1997214.

It is an interprime number because it is at equal distance from previous prime (4127989) and next prime (4127993).

It is not a de Polignac number, because 4127991 - 2¹ = 4127989 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (4127993) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10881 + ... + 11253.

It is an arithmetic number, because the mean of its divisors is an integer number (215424).

Almost surely, 2^4127991 is an apocalyptic number.

4127991 is a deficient number, since it is larger than the sum of its proper divisors (2765577).

4127991 is a wasteful number, since it uses less digits than its factorization.

4127991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 431.

The product of its digits is 4536, while the sum is 33.

The square root of 4127991 is about 2031.7458010293. The cubic root of 4127991 is about 160.4154697012.

The spelling of 4127991 in words is "four million, one hundred twenty-seven thousand, nine hundred ninety-one".