1311230220 has 48 divisors (see below), whose sum is σ = 3673016928. Its totient is φ = 349511680.

The previous prime is 1311230209. The next prime is 1311230251. The reversal of 1311230220 is 220321131.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 1311230220.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 266422 + ... + 271298.

It is an arithmetic number, because the mean of its divisors is an integer number (76521186).

Almost surely, 2^1311230220 is an apocalyptic number.

1311230220 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1311230220 is an abundant number, since it is smaller than the sum of its proper divisors (2361786708).

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

1311230220 is a wasteful number, since it uses less digits than its factorization.

1311230220 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 9370 (or 9368 counting only the distinct ones).

The product of its (nonzero) digits is 72, while the sum is 15.

The square root of 1311230220 is about 36210.9129959464. The cubic root of 1311230220 is about 1094.5265900438.

Adding to 1311230220 its reverse (220321131), we get a palindrome (1531551351).

The spelling of 1311230220 in words is "one billion, three hundred eleven million, two hundred thirty thousand, two hundred twenty".