7126991 has 4 divisors (see below), whose sum is σ = 7233432. Its totient is φ = 7020552.

The previous prime is 7126981. The next prime is 7126997. The reversal of 7126991 is 1996217.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-7126991 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 (7126997) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53120 + ... + 53253.

It is an arithmetic number, because the mean of its divisors is an integer number (1808358).

Almost surely, 2^7126991 is an apocalyptic number.

7126991 is a deficient number, since it is larger than the sum of its proper divisors (106441).

7126991 is a wasteful number, since it uses less digits than its factorization.

7126991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 106440.

The product of its digits is 6804, while the sum is 35.

The square root of 7126991 is about 2669.6424854276. The cubic root of 7126991 is about 192.4429785572.

The spelling of 7126991 in words is "seven million, one hundred twenty-six thousand, nine hundred ninety-one".