1005505561000 has 128 divisors (see below), whose sum is σ = 2365483629600. Its totient is φ = 400053043200.

The previous prime is 1005505560991. The next prime is 1005505561009. The reversal of 1005505561000 is 1655055001.

It is an interprime number because it is at equal distance from previous prime (1005505560991) and next prime (1005505561009).

It can be written as a sum of positive squares in 16 ways, for example, as 197984062116 + 807521498884 = 444954^2 + 898622^2 .

It is a super-2 number, since 2×1005505561000² (a number of 25 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 1005505561000.

It is not an unprimeable number, because it can be changed into a prime (1005505561009) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 204826546 + ... + 204831454.

Almost surely, 2^{1005505561000} is an apocalyptic number.

1005505561000 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 1005505561000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (1182741814800).

1005505561000 is an abundant number, since it is smaller than the sum of its proper divisors (1359978068600).

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

1005505561000 is a wasteful number, since it uses less digits than its factorization.

1005505561000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5984 (or 5970 counting only the distinct ones).

The product of its (nonzero) digits is 3750, while the sum is 28.

The spelling of 1005505561000 in words is "one trillion, five billion, five hundred five million, five hundred sixty-one thousand".