1131256542 has 64 divisors (see below), whose sum is σ = 2603301120. Its totient is φ = 324808704.

The previous prime is 1131256507. The next prime is 1131256571. The reversal of 1131256542 is 2456521311.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 93598 + ... + 104990.

It is an arithmetic number, because the mean of its divisors is an integer number (40676580).

Almost surely, 2^1131256542 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1131256542, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1301650560).

1131256542 is an abundant number, since it is smaller than the sum of its proper divisors (1472044578).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1131256542 is a wasteful number, since it uses less digits than its factorization.

1131256542 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11497.

The product of its digits is 7200, while the sum is 30.

The square root of 1131256542 is about 33634.1573701498. The cubic root of 1131256542 is about 1041.9663679106.

Adding to 1131256542 its reverse (2456521311), we get a palindrome (3587777853).

The spelling of 1131256542 in words is "one billion, one hundred thirty-one million, two hundred fifty-six thousand, five hundred forty-two".