1001165550 has 384 divisors, whose sum is σ = 3321216000. Its totient is φ = 197568000.

The previous prime is 1001165549. The next prime is 1001165591. The reversal of 1001165550 is 555611001.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 1001165550.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 191 ways as a sum of consecutive naturals, for example, 16412520 + ... + 16412580.

It is an arithmetic number, because the mean of its divisors is an integer number (8649000).

Almost surely, 2^1001165550 is an apocalyptic number.

1001165550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 1001165550, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1660608000).

1001165550 is an abundant number, since it is smaller than the sum of its proper divisors (2320050450).

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

1001165550 is a wasteful number, since it uses less digits than its factorization.

1001165550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 137 (or 118 counting only the distinct ones).

The product of its (nonzero) digits is 750, while the sum is 24.

The square root of 1001165550 is about 31641.2001984754. The cubic root of 1001165550 is about 1000.3883658191.

Adding to 1001165550 its reverse (555611001), we get a palindrome (1556776551).

The spelling of 1001165550 in words is "one billion, one million, one hundred sixty-five thousand, five hundred fifty".