1217491 has 4 divisors (see below), whose sum is σ = 1328184. Its totient is φ = 1106800.

The previous prime is 1217483. The next prime is 1217509. The reversal of 1217491 is 1947121.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1947121 = 11 ⋅177011.

It is a cyclic number.

It is not a de Polignac number, because 1217491 - 2³ = 1217483 is a prime.

It is a d-powerful number, because it can be written as 1 + 2¹⁷ + 1 + 7⁷ + 4⁹ + 9³ + 1 .

It is a plaindrome in base 14.

It is not an unprimeable number, because it can be changed into a prime (1217471) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55330 + ... + 55351.

It is an arithmetic number, because the mean of its divisors is an integer number (332046).

2^1217491 is an apocalyptic number.

1217491 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

1217491 is a deficient number, since it is larger than the sum of its proper divisors (110693).

1217491 is a wasteful number, since it uses less digits than its factorization.

1217491 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 110692.

The product of its digits is 504, while the sum is 25.

The square root of 1217491 is about 1103.3997462389. The cubic root of 1217491 is about 106.7796729867.

The spelling of 1217491 in words is "one million, two hundred seventeen thousand, four hundred ninety-one".