1611166165501 has 2 divisors, whose sum is σ = 1611166165502. Its totient is φ = 1611166165500.

The previous prime is 1611166165487. The next prime is 1611166165517. The reversal of 1611166165501 is 1055616611161.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1000502063001 + 610664102500 = 1000251^2 + 781450^2 .

It is a cyclic number.

It is not a de Polignac number, because 1611166165501 - 2⁹ = 1611166164989 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1611166165591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 805583082750 + 805583082751.

It is an arithmetic number, because the mean of its divisors is an integer number (805583082751).

Almost surely, 2^{1611166165501} is an apocalyptic number.

It is an amenable number.

1611166165501 is a deficient number, since it is larger than the sum of its proper divisors (1).

1611166165501 is an equidigital number, since it uses as much as digits as its factorization.

1611166165501 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 32400, while the sum is 40.

The spelling of 1611166165501 in words is "one trillion, six hundred eleven billion, one hundred sixty-six million, one hundred sixty-five thousand, five hundred one".