1005556661205 has 16 divisors (see below), whose sum is σ = 1678842426240. Its totient is φ = 512979629888.

The previous prime is 1005556661203. The next prime is 1005556661261. The reversal of 1005556661205 is 5021666555001.

It is a cyclic number.

It is not a de Polignac number, because 1005556661205 - 2¹ = 1005556661203 is a prime.

It is a super-2 number, since 2×1005556661205² (a number of 25 digits) contains 22 as substring.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1005556661203) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1457328150 + ... + 1457328839.

It is an arithmetic number, because the mean of its divisors is an integer number (104927651640).

Almost surely, 2^{1005556661205} is an apocalyptic number.

1005556661205 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

1005556661205 is a deficient number, since it is larger than the sum of its proper divisors (673285765035).

1005556661205 is a wasteful number, since it uses less digits than its factorization.

1005556661205 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2914657020.

The product of its (nonzero) digits is 270000, while the sum is 42.

The spelling of 1005556661205 in words is "one trillion, five billion, five hundred fifty-six million, six hundred sixty-one thousand, two hundred five".