1165004991000 has 256 divisors, whose sum is σ = 4095573580800. Its totient is φ = 306291888000.

The previous prime is 1165004990987. The next prime is 1165004991037. The reversal of 1165004991000 is 1994005611.

1165004991000 is a `hidden beast` number, since 1 + 1 + 6 + 500 + 49 + 9 + 100 + 0 = 666.

It is a Harshad number since it is a multiple of its sum of digits (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 1613139 + ... + 2220861.

It is an arithmetic number, because the mean of its divisors is an integer number (15998334300).

Almost surely, 2^{1165004991000} is an apocalyptic number.

1165004991000 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 1165004991000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2047786790400).

1165004991000 is an abundant number, since it is smaller than the sum of its proper divisors (2930568589800).

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

1165004991000 is a wasteful number, since it uses less digits than its factorization.

1165004991000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 607824 (or 607804 counting only the distinct ones).

The product of its (nonzero) digits is 9720, while the sum is 36.

Adding to 1165004991000 its reverse (1994005611), we get a palindrome (1166998996611).

The spelling of 1165004991000 in words is "one trillion, one hundred sixty-five billion, four million, nine hundred ninety-one thousand".