16666798085001 has 45 divisors (see below), whose sum is σ = 26449004749431. Its totient is φ = 10457206878528.

The previous prime is 16666798084987. The next prime is 16666798085027. The reversal of 16666798085001 is 10058089766661.

The square root of 16666798085001 is 4082499.

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., 12975880862025 + 3690917222976 = 3602205^2 + 1921176^2 .

It is not a de Polignac number, because 16666798085001 - 2³¹ = 16664650601353 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 16666798085001.

It is not an unprimeable number, because it can be changed into a prime (16666798085051) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 44 ways as a sum of consecutive naturals, for example, 624609006 + ... + 624635688.

Almost surely, 2^{16666798085001} is an apocalyptic number.

16666798085001 is the 4082499-th square number.

16666798085001 is the 2041250-th centered octagonal number.

It is an amenable number.

16666798085001 is a deficient number, since it is larger than the sum of its proper divisors (9782206664430).

16666798085001 is an frugal number, since it uses more digits than its factorization.

16666798085001 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 53412 (or 26703 counting only the distinct ones).

The product of its (nonzero) digits is 26127360, while the sum is 63.

The spelling of 16666798085001 in words is "sixteen trillion, six hundred sixty-six billion, seven hundred ninety-eight million, eighty-five thousand, one".