1661615155166 has 16 divisors (see below), whose sum is σ = 2494642396560. Its totient is φ = 830067860160.

The previous prime is 1661615155103. The next prime is 1661615155169. The reversal of 1661615155166 is 6615515161661.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1661615155169) 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, 21935705 + ... + 22011323.

It is an arithmetic number, because the mean of its divisors is an integer number (155915149785).

Almost surely, 2^{1661615155166} is an apocalyptic number.

1661615155166 is a deficient number, since it is larger than the sum of its proper divisors (833027241394).

1661615155166 is a wasteful number, since it uses less digits than its factorization.

1661615155166 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 85259.

The product of its digits is 972000, while the sum is 50.

The spelling of 1661615155166 in words is "one trillion, six hundred sixty-one billion, six hundred fifteen million, one hundred fifty-five thousand, one hundred sixty-six".