1131299999 has 4 divisors (see below), whose sum is σ = 1152645336. Its totient is φ = 1109954664.

The previous prime is 1131299989. The next prime is 1131300007. The reversal of 1131299999 is 9999921311.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 9999921311 = 16451 ⋅607861.

It is a cyclic number.

It is not a de Polignac number, because 1131299999 - 2¹⁶ = 1131234463 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (53), and also a Moran number because the ratio is a prime number: 21345283 = 1131299999 / (1 + 1 + 3 + 1 + 2 + 9 + 9 + 9 + 9 + 9).

It is a Duffinian number.

1131299999 is a modest number, since divided by 99999 gives 11312 as remainder.

It is a self number, because there is not a number n which added to its sum of digits gives 1131299999.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1131299989) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10672589 + ... + 10672694.

It is an arithmetic number, because the mean of its divisors is an integer number (288161334).

Almost surely, 2^1131299999 is an apocalyptic number.

1131299999 is a deficient number, since it is larger than the sum of its proper divisors (21345337).

1131299999 is an equidigital number, since it uses as much as digits as its factorization.

1131299999 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21345336.

The product of its digits is 354294, while the sum is 53.

The square root of 1131299999 is about 33634.8033887520. The cubic root of 1131299999 is about 1041.9797100515.

The spelling of 1131299999 in words is "one billion, one hundred thirty-one million, two hundred ninety-nine thousand, nine hundred ninety-nine".