91026 has 24 divisors (see below), whose sum is σ = 212940. Its totient is φ = 27936.

The previous prime is 91019. The next prime is 91033. The reversal of 91026 is 62019.

It is an interprime number because it is at equal distance from previous prime (91019) and next prime (91033).

It can be written as a sum of positive squares in 2 ways, for example, as 81225 + 9801 = 285^2 + 99^2 .

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an unprimeable number.

91026 is an untouchable number, because it is not equal to the sum of proper divisors of any number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 40 + ... + 428.

2⁹¹⁰²⁶ is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 91026, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (106470).

91026 is an abundant number, since it is smaller than the sum of its proper divisors (121914).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91026 is a wasteful number, since it uses less digits than its factorization.

91026 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 410 (or 407 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 18.

The square root of 91026 is about 301.7051540826. The cubic root of 91026 is about 44.9836977986.

It can be divided in two parts, 9 and 1026, that added together give a triangular number (1035 = T₄₅).

The spelling of 91026 in words is "ninety-one thousand, twenty-six".