10000991 has 32 divisors (see below), whose sum is σ = 13698048. Its totient is φ = 7050240.

The previous prime is 10000987. The next prime is 10000993. The reversal of 10000991 is 19900001.

It is a cyclic number.

It is not a de Polignac number, because 10000991 - 2² = 10000987 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (10000993) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 97046 + ... + 97148.

It is an arithmetic number, because the mean of its divisors is an integer number (428064).

Almost surely, 2^10000991 is an apocalyptic number.

10000991 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

10000991 is a deficient number, since it is larger than the sum of its proper divisors (3697057).

10000991 is a wasteful number, since it uses less digits than its factorization.

10000991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 231.

The product of its (nonzero) digits is 81, while the sum is 20.

The square root of 10000991 is about 3162.4343471446. The cubic root of 10000991 is about 215.4505855840.

Adding to 10000991 its reverse (19900001), we get a palindrome (29900992).

The spelling of 10000991 in words is "ten million, nine hundred ninety-one", and thus it is an aban number.