1209491 has 2 divisors, whose sum is σ = 1209492. Its totient is φ = 1209490.

The previous prime is 1209487. The next prime is 1209517. The reversal of 1209491 is 1949021.

It is an a-pointer prime, because the next prime (1209517) can be obtained adding 1209491 to its sum of digits (26).

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 1209491 - 2² = 1209487 is a prime.

It is a plaindrome in base 13.

It is a self number, because there is not a number n which added to its sum of digits gives 1209491.

It is not a weakly prime, because it can be changed into another prime (1209191) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 604745 + 604746.

It is an arithmetic number, because the mean of its divisors is an integer number (604746).

2^1209491 is an apocalyptic number.

1209491 is a deficient number, since it is larger than the sum of its proper divisors (1).

1209491 is an equidigital number, since it uses as much as digits as its factorization.

1209491 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 648, while the sum is 26.

The square root of 1209491 is about 1099.7686120271. The cubic root of 1209491 is about 106.5452796653.

The spelling of 1209491 in words is "one million, two hundred nine thousand, four hundred ninety-one".