1131551 has 4 divisors (see below), whose sum is σ = 1170600. Its totient is φ = 1092504.

The previous prime is 1131547. The next prime is 1131553. The reversal of 1131551 is 1551311.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1131551 - 2² = 1131547 is a prime.

It is a Duffinian number.

It is a plaindrome in base 12.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131553) 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, 19481 + ... + 19538.

It is an arithmetic number, because the mean of its divisors is an integer number (292650).

2^1131551 is an apocalyptic number.

1131551 is a deficient number, since it is larger than the sum of its proper divisors (39049).

1131551 is an equidigital number, since it uses as much as digits as its factorization.

1131551 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 39048.

The product of its digits is 75, while the sum is 17.

The square root of 1131551 is about 1063.7438601468. The cubic root of 1131551 is about 104.2056765536.

Adding to 1131551 its reverse (1551311), we get a palindrome (2682862).

The spelling of 1131551 in words is "one million, one hundred thirty-one thousand, five hundred fifty-one".