1131991200 has 288 divisors, whose sum is σ = 4150984320. Its totient is φ = 301397760.

The previous prime is 1131991183. The next prime is 1131991241. The reversal of 1131991200 is 21991311.

It is a tau number, because it is divible by the number of its divisors (288).

It is a hoax number, since the sum of its digits (27) coincides with the sum of the digits of its distinct prime factors.

It is a Harshad number since it is a multiple of its sum of digits (27).

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, 1749277 + ... + 1749923.

It is an arithmetic number, because the mean of its divisors is an integer number (14413140).

Almost surely, 2^1131991200 is an apocalyptic number.

1131991200 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 1131991200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2075492160).

1131991200 is an abundant number, since it is smaller than the sum of its proper divisors (3018993120).

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

1131991200 is an frugal number, since it uses more digits than its factorization.

1131991200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 688 (or 657 counting only the distinct ones).

The product of its (nonzero) digits is 486, while the sum is 27.

The square root of 1131991200 is about 33645.0769058417. The cubic root of 1131991200 is about 1042.1918762287.

The spelling of 1131991200 in words is "one billion, one hundred thirty-one million, nine hundred ninety-one thousand, two hundred".