1231323100 has 144 divisors (see below), whose sum is σ = 3179796480. Its totient is φ = 404985600.

The previous prime is 1231323089. The next prime is 1231323167. The reversal of 1231323100 is 13231321.

It is a super-2 number, since 2×1231323100² = 3032313153187220000, which contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 3884142 + ... + 3884458.

It is an arithmetic number, because the mean of its divisors is an integer number (22081920).

Almost surely, 2^1231323100 is an apocalyptic number.

1231323100 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 1231323100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1589898240).

1231323100 is an abundant number, since it is smaller than the sum of its proper divisors (1948473380).

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

1231323100 is a wasteful number, since it uses less digits than its factorization.

1231323100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 548 (or 541 counting only the distinct ones).

The product of its (nonzero) digits is 108, while the sum is 16.

The square root of 1231323100 is about 35090.2137354562. The cubic root of 1231323100 is about 1071.8253119507.

Adding to 1231323100 its reverse (13231321), we get a palindrome (1244554421).

The spelling of 1231323100 in words is "one billion, two hundred thirty-one million, three hundred twenty-three thousand, one hundred".