1026991 has 6 divisors (see below), whose sum is σ = 1194720. Its totient is φ = 880236.

The previous prime is 1026989. The next prime is 1027001. The reversal of 1026991 is 1996201.

1026991 is nontrivially palindromic in base 16.

It is not a de Polignac number, because 1026991 - 2¹ = 1026989 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 (1026911) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 10431 + ... + 10528.

It is an arithmetic number, because the mean of its divisors is an integer number (199120).

2^1026991 is an apocalyptic number.

1026991 is a deficient number, since it is larger than the sum of its proper divisors (167729).

1026991 is an equidigital number, since it uses as much as digits as its factorization.

1026991 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20973 (or 20966 counting only the distinct ones).

The product of its (nonzero) digits is 972, while the sum is 28.

The square root of 1026991 is about 1013.4056443498. The cubic root of 1026991 is about 100.8917246359.

The spelling of 1026991 in words is "one million, twenty-six thousand, nine hundred ninety-one".