16866476641 has 9 divisors (see below), whose sum is σ = 19621244691. Its totient is φ = 14456200752.

The previous prime is 16866476623. The next prime is 16866476651. The reversal of 16866476641 is 14667466861.

The square root of 16866476641 is 129871.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in only one way, i.e., 1117230625 + 15749246016 = 33425^2 + 125496^2 .

It is not a de Polignac number, because 16866476641 - 2⁷ = 16866476513 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (16866476651) by changing a digit.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 899821 + ... + 918373.

It is an arithmetic number, because the mean of its divisors is an integer number (2180138299).

Almost surely, 2^16866476641 is an apocalyptic number.

16866476641 is the 129871-st square number.

16866476641 is the 64936-th centered octagonal number.

It is an amenable number.

16866476641 is a deficient number, since it is larger than the sum of its proper divisors (2754768050).

16866476641 is an frugal number, since it uses more digits than its factorization.

16866476641 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 37120 (or 18560 counting only the distinct ones).

The product of its digits is 6967296, while the sum is 55.

The spelling of 16866476641 in words is "sixteen billion, eight hundred sixty-six million, four hundred seventy-six thousand, six hundred forty-one".