1661665616006 has 12 divisors (see below), whose sum is σ = 2739688350756. Its totient is φ = 755302552620.

The previous prime is 1661665615993. The next prime is 1661665616033. The reversal of 1661665616006 is 6006165661661.

It is a happy number.

It is a super-2 number, since 2×1661665616006² (a number of 25 digits) contains 22 as substring.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 3433193180 + ... + 3433193663.

It is an arithmetic number, because the mean of its divisors is an integer number (228307362563).

Almost surely, 2^{1661665616006} is an apocalyptic number.

1661665616006 is a deficient number, since it is larger than the sum of its proper divisors (1078022734750).

1661665616006 is a wasteful number, since it uses less digits than its factorization.

1661665616006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6866386867 (or 6866386856 counting only the distinct ones).

The product of its (nonzero) digits is 1399680, while the sum is 50.

The spelling of 1661665616006 in words is "one trillion, six hundred sixty-one billion, six hundred sixty-five million, six hundred sixteen thousand, six".