1131240220 has 96 divisors (see below), whose sum is σ = 2748082176. Its totient is φ = 387244800.

The previous prime is 1131240191. The next prime is 1131240269. The reversal of 1131240220 is 220421311.

It is a junction number, because it is equal to n+sod(n) for n = 1131240194 and 1131240203.

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, 250099 + ... + 254581.

It is an arithmetic number, because the mean of its divisors is an integer number (28625856).

Almost surely, 2^1131240220 is an apocalyptic number.

1131240220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 1131240220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1374041088).

1131240220 is an abundant number, since it is smaller than the sum of its proper divisors (1616841956).

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

1131240220 is a wasteful number, since it uses less digits than its factorization.

1131240220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4571 (or 4569 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 1131240220 is about 33633.9147290350. The cubic root of 1131240220 is about 1041.9613566521.

Adding to 1131240220 its reverse (220421311), we get a palindrome (1351661531).

The spelling of 1131240220 in words is "one billion, one hundred thirty-one million, two hundred forty thousand, two hundred twenty".