16724705661 has 16 divisors (see below), whose sum is σ = 25116760320. Its totient is φ = 10997065440.

The previous prime is 16724705639. The next prime is 16724705671. The reversal of 16724705661 is 16650742761.

16724705661 is a `hidden beast` number, since 1 + 6 + 72 + 470 + 56 + 61 = 666.

It is not a de Polignac number, because 16724705661 - 2⁵ = 16724705629 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (16724705671) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 4240725 + ... + 4244666.

It is an arithmetic number, because the mean of its divisors is an integer number (1569797520).

Almost surely, 2^16724705661 is an apocalyptic number.

It is an amenable number.

16724705661 is a deficient number, since it is larger than the sum of its proper divisors (8392054659).

16724705661 is an equidigital number, since it uses as much as digits as its factorization.

16724705661 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8485473 (or 8485467 counting only the distinct ones).

The product of its (nonzero) digits is 423360, while the sum is 45.

The spelling of 16724705661 in words is "sixteen billion, seven hundred twenty-four million, seven hundred five thousand, six hundred sixty-one".