16666000 has 80 divisors (see below), whose sum is σ = 43465968. Its totient is φ = 6144000.

The previous prime is 16665953. The next prime is 16666019. The reversal of 16666000 is 66661.

It can be written as a sum of positive squares in 8 ways, for example, as 4804864 + 11861136 = 2192^2 + 3444^2 .

It is a tau number, because it is divible by the number of its divisors (80).

It is a Harshad number since it is a multiple of its sum of digits (25).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 25680 + ... + 26320.

Almost surely, 2^16666000 is an apocalyptic number.

16666000 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 16666000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21732984).

16666000 is an abundant number, since it is smaller than the sum of its proper divisors (26799968).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

16666000 is a wasteful number, since it uses less digits than its factorization.

16666000 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 677 (or 661 counting only the distinct ones).

The product of its (nonzero) digits is 1296, while the sum is 25.

The square root of 16666000 is about 4082.4012541640. The cubic root of 16666000 is about 255.4330715994.

It can be divided in two parts, 166 and 66000, that added together give a palindrome (66166).

The spelling of 16666000 in words is "sixteen million, six hundred sixty-six thousand".