1556666660550 has 24 divisors (see below), whose sum is σ = 3860533318536. Its totient is φ = 415111109440.

The previous prime is 1556666660539. The next prime is 1556666660557. The reversal of 1556666660550 is 550666666551.

It is a super-2 number, since 2×1556666660550² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1556666660557) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5188888719 + ... + 5188889018.

It is an arithmetic number, because the mean of its divisors is an integer number (160855554939).

Almost surely, 2^{1556666660550} is an apocalyptic number.

1556666660550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

1556666660550 is an abundant number, since it is smaller than the sum of its proper divisors (2303866657986).

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

1556666660550 is a wasteful number, since it uses less digits than its factorization.

1556666660550 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10377777752 (or 10377777747 counting only the distinct ones).

The product of its (nonzero) digits is 29160000, while the sum is 57.

The spelling of 1556666660550 in words is "one trillion, five hundred fifty-six billion, six hundred sixty-six million, six hundred sixty thousand, five hundred fifty".