1311223100 has 72 divisors (see below), whose sum is σ = 3239042688. Its totient is φ = 456068800.

The previous prime is 1311223093. The next prime is 1311223129. The reversal of 1311223100 is 13221131.

It is a super-2 number, since 2×1311223100² = 3438612035947220000, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 614 + ... + 51213.

It is an arithmetic number, because the mean of its divisors is an integer number (44986704).

Almost surely, 2^1311223100 is an apocalyptic number.

1311223100 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 1311223100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1619521344).

1311223100 is an abundant number, since it is smaller than the sum of its proper divisors (1927819588).

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

1311223100 is a wasteful number, since it uses less digits than its factorization.

1311223100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 51875 (or 51868 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 14.

The square root of 1311223100 is about 36210.8146829093. The cubic root of 1311223100 is about 1094.5246089415.

Adding to 1311223100 its reverse (13221131), we get a palindrome (1324444231).

The spelling of 1311223100 in words is "one billion, three hundred eleven million, two hundred twenty-three thousand, one hundred".