11661503 has 4 divisors (see below), whose sum is σ = 13327440. Its totient is φ = 9995568.

The previous prime is 11661491. The next prime is 11661523. The reversal of 11661503 is 30516611.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 30516611 = 479 ⋅63709.

It is a cyclic number.

It is not a de Polignac number, because 11661503 - 2¹⁶ = 11595967 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11661523) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 832958 + ... + 832971.

It is an arithmetic number, because the mean of its divisors is an integer number (3331860).

Almost surely, 2^11661503 is an apocalyptic number.

11661503 is a deficient number, since it is larger than the sum of its proper divisors (1665937).

11661503 is an equidigital number, since it uses as much as digits as its factorization.

11661503 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1665936.

The product of its (nonzero) digits is 540, while the sum is 23.

The square root of 11661503 is about 3414.8942882614. The cubic root of 11661503 is about 226.7696045809.

The spelling of 11661503 in words is "eleven million, six hundred sixty-one thousand, five hundred three".