1491109 has 2 divisors, whose sum is σ = 1491110. Its totient is φ = 1491108.

The previous prime is 1491103. The next prime is 1491157. The reversal of 1491109 is 9011941.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1476225 + 14884 = 1215^2 + 122^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1491109 is a prime.

1491109 is a lucky number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1491103) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 745554 + 745555.

It is an arithmetic number, because the mean of its divisors is an integer number (745555).

2^1491109 is an apocalyptic number.

It is an amenable number.

1491109 is a deficient number, since it is larger than the sum of its proper divisors (1).

1491109 is an equidigital number, since it uses as much as digits as its factorization.

1491109 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 324, while the sum is 25.

The square root of 1491109 is about 1221.1097411781. The cubic root of 1491109 is about 114.2448058199.

It can be divided in two parts, 1491 and 109, that added together give a square (1600 = 40²).

The spelling of 1491109 in words is "one million, four hundred ninety-one thousand, one hundred nine".