1009491 has 16 divisors (see below), whose sum is σ = 1569024. Its totient is φ = 565344.

The previous prime is 1009487. The next prime is 1009499. The reversal of 1009491 is 1949001.

It is not a de Polignac number, because 1009491 - 2² = 1009487 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1009499) 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 15 ways as a sum of consecutive naturals, for example, 660 + ... + 1566.

It is an arithmetic number, because the mean of its divisors is an integer number (98064).

2^1009491 is an apocalyptic number.

1009491 is a deficient number, since it is larger than the sum of its proper divisors (559533).

1009491 is an equidigital number, since it uses as much as digits as its factorization.

1009491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 970.

The product of its (nonzero) digits is 324, while the sum is 24.

The square root of 1009491 is about 1004.7342932338. The cubic root of 1009491 is about 100.3153710322.

It can be divided in two parts, 100 and 9491, that added together give a triangular number (9591 = T₁₃₈).

The spelling of 1009491 in words is "one million, nine thousand, four hundred ninety-one".