1131221544 has 32 divisors (see below), whose sum is σ = 2976900000. Its totient is φ = 357227712.

The previous prime is 1131221543. The next prime is 1131221557. The reversal of 1131221544 is 4451221311.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is not an unprimeable number, because it can be changed into a prime (1131221543) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1239919 + ... + 1240830.

It is an arithmetic number, because the mean of its divisors is an integer number (93028125).

Almost surely, 2^1131221544 is an apocalyptic number.

It is an amenable number.

1131221544 is an abundant number, since it is smaller than the sum of its proper divisors (1845678456).

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

1131221544 is a wasteful number, since it uses less digits than its factorization.

1131221544 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2480777 (or 2480773 counting only the distinct ones).

The product of its digits is 960, while the sum is 24.

The square root of 1131221544 is about 33633.6370914595. The cubic root of 1131221544 is about 1041.9556225981.

Adding to 1131221544 its reverse (4451221311), we get a palindrome (5582442855).

The spelling of 1131221544 in words is "one billion, one hundred thirty-one million, two hundred twenty-one thousand, five hundred forty-four".