11481551 has 4 divisors (see below), whose sum is σ = 11488512. Its totient is φ = 11474592.

The previous prime is 11481527. The next prime is 11481553. The reversal of 11481551 is 15518411.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 11481551 - 2⁶ = 11481487 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 11481551.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11481553) 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, 551 + ... + 4823.

It is an arithmetic number, because the mean of its divisors is an integer number (2872128).

Almost surely, 2^11481551 is an apocalyptic number.

11481551 is a deficient number, since it is larger than the sum of its proper divisors (6961).

11481551 is an equidigital number, since it uses as much as digits as its factorization.

11481551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6960.

The product of its digits is 800, while the sum is 26.

The square root of 11481551 is about 3388.4437430773. The cubic root of 11481551 is about 225.5971037198.

Adding to 11481551 its reverse (15518411), we get a palindrome (26999962).

The spelling of 11481551 in words is "eleven million, four hundred eighty-one thousand, five hundred fifty-one".