1000005561 has 8 divisors (see below), whose sum is σ = 1481489760. Its totient is φ = 666670356.

The previous prime is 1000005547. The next prime is 1000005583. The reversal of 1000005561 is 1655000001.

1000005561 is a `hidden beast` number, since 100 + 0 + 0 + 0 + 5 + 561 = 666.

It is not a de Polignac number, because 1000005561 - 2¹¹ = 1000003513 is a prime.

It is a super-2 number, since 2×1000005561² = 2000022244061849442, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (1000005541) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 18518595 + ... + 18518648.

It is an arithmetic number, because the mean of its divisors is an integer number (185186220).

Almost surely, 2^1000005561 is an apocalyptic number.

It is an amenable number.

1000005561 is a deficient number, since it is larger than the sum of its proper divisors (481484199).

1000005561 is an equidigital number, since it uses as much as digits as its factorization.

1000005561 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37037252 (or 37037246 counting only the distinct ones).

The product of its (nonzero) digits is 150, while the sum is 18.

The square root of 1000005561 is about 31622.8645286919. The cubic root of 1000005561 is about 1000.0018536632.

Adding to 1000005561 its reverse (1655000001), we get a palindrome (2655005562).

The spelling of 1000005561 in words is "one billion, five thousand, five hundred sixty-one".