10831991 has 4 divisors (see below), whose sum is σ = 10866912. Its totient is φ = 10797072.

The previous prime is 10831969. The next prime is 10832023. The reversal of 10831991 is 19913801.

10831991 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

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

It is a cyclic number.

It is not a de Polignac number, because 10831991 - 2¹⁸ = 10569847 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 (10831391) 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, 16991 + ... + 17616.

It is an arithmetic number, because the mean of its divisors is an integer number (2716728).

Almost surely, 2^10831991 is an apocalyptic number.

10831991 is a deficient number, since it is larger than the sum of its proper divisors (34921).

10831991 is an equidigital number, since it uses as much as digits as its factorization.

10831991 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 34920.

The product of its (nonzero) digits is 1944, while the sum is 32.

The square root of 10831991 is about 3291.1990216333. The cubic root of 10831991 is about 221.2599263530.

The spelling of 10831991 in words is "ten million, eight hundred thirty-one thousand, nine hundred ninety-one".