1231001100 has 216 divisors, whose sum is σ = 4529758688. Its totient is φ = 273715200.

The previous prime is 1231001071. The next prime is 1231001131. The reversal of 1231001100 is 11001321.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a nialpdrome in base 15.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 230460 + ... + 235740.

Almost surely, 2^1231001100 is an apocalyptic number.

1231001100 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 1231001100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2264879344).

1231001100 is an abundant number, since it is smaller than the sum of its proper divisors (3298757588).

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

1231001100 is a wasteful number, since it uses less digits than its factorization.

1231001100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5345 (or 5335 counting only the distinct ones).

The product of its (nonzero) digits is 6, while the sum is 9.

The square root of 1231001100 is about 35085.6252616367. The cubic root of 1231001100 is about 1071.7318737515.

Adding to 1231001100 its reverse (11001321), we get a palindrome (1242002421).

The spelling of 1231001100 in words is "one billion, two hundred thirty-one million, one thousand, one hundred".