1001005520 has 20 divisors (see below), whose sum is σ = 2327338020. Its totient is φ = 400402176.

The previous prime is 1001005459. The next prime is 1001005549. The reversal of 1001005520 is 255001001.

It can be written as a sum of positive squares in 2 ways, for example, as 442345024 + 558660496 = 21032^2 + 23636^2 .

It is a tau number, because it is divible by the number of its divisors (20).

It is a junction number, because it is equal to n+sod(n) for n = 1001005495 and 1001005504.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 6256205 + ... + 6256364.

It is an arithmetic number, because the mean of its divisors is an integer number (116366901).

Almost surely, 2^1001005520 is an apocalyptic number.

1001005520 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

1001005520 is an abundant number, since it is smaller than the sum of its proper divisors (1326332500).

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

1001005520 is a wasteful number, since it uses less digits than its factorization.

1001005520 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12512582 (or 12512576 counting only the distinct ones).

The product of its (nonzero) digits is 50, while the sum is 14.

The square root of 1001005520 is about 31638.6712742492. The cubic root of 1001005520 is about 1000.3350610549.

Adding to 1001005520 its reverse (255001001), we get a palindrome (1256006521).

The spelling of 1001005520 in words is "one billion, one million, five thousand, five hundred twenty".