16605034661 has 4 divisors (see below), whose sum is σ = 16629708492. Its totient is φ = 16580360832.

The previous prime is 16605034643. The next prime is 16605034669. The reversal of 16605034661 is 16643050661.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 6888004036 + 9717030625 = 82994^2 + 98575^2 .

It is a cyclic number.

It is not a de Polignac number, because 16605034661 - 2¹⁰ = 16605033637 is a prime.

It is a super-2 number, since 2×16605034661² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16605034669) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 12335906 + ... + 12337251.

It is an arithmetic number, because the mean of its divisors is an integer number (4157427123).

Almost surely, 2^16605034661 is an apocalyptic number.

It is an amenable number.

16605034661 is a deficient number, since it is larger than the sum of its proper divisors (24673831).

16605034661 is an equidigital number, since it uses as much as digits as its factorization.

16605034661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 24673830.

The product of its (nonzero) digits is 77760, while the sum is 38.

The spelling of 16605034661 in words is "sixteen billion, six hundred five million, thirty-four thousand, six hundred sixty-one".