1311240220 has 24 divisors (see below), whose sum is σ = 2848557600. Its totient is φ = 506409792.

The previous prime is 1311240211. The next prime is 1311240221. The reversal of 1311240220 is 220421131.

It is a junction number, because it is equal to n+sod(n) for n = 1311240194 and 1311240203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1311240221) 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, 1129800 + ... + 1130959.

It is an arithmetic number, because the mean of its divisors is an integer number (118689900).

Almost surely, 2^1311240220 is an apocalyptic number.

1311240220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1311240220 is an abundant number, since it is smaller than the sum of its proper divisors (1537317380).

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

1311240220 is a wasteful number, since it uses less digits than its factorization.

1311240220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2260797 (or 2260795 counting only the distinct ones).

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

The square root of 1311240220 is about 36211.0510756040. The cubic root of 1311240220 is about 1094.5293724787.

Adding to 1311240220 its reverse (220421131), we get a palindrome (1531661351).

The spelling of 1311240220 in words is "one billion, three hundred eleven million, two hundred forty thousand, two hundred twenty".