16661700 has 270 divisors, whose sum is σ = 62859258. Its totient is φ = 3801600.

The previous prime is 16661681. The next prime is 16661707. The reversal of 16661700 is 716661.

It can be written as a sum of positive squares in 3 ways, for example, as 2509056 + 14152644 = 1584^2 + 3762^2 .

It is a tau number, because it is divible by the number of its divisors (270).

It is a super-2 number, since 2×16661700² = 555224493780000, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is not an unprimeable number, because it can be changed into a prime (16661707) by changing a digit.

It is a polite number, since it can be written in 89 ways as a sum of consecutive naturals, for example, 980092 + ... + 980108.

Almost surely, 2^16661700 is an apocalyptic number.

16661700 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 16661700, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (31429629).

16661700 is an abundant number, since it is smaller than the sum of its proper divisors (46197558).

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

16661700 is a wasteful number, since it uses less digits than its factorization.

16661700 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 65 (or 38 counting only the distinct ones).

The product of its (nonzero) digits is 1512, while the sum is 27.

The square root of 16661700 is about 4081.8745693615. The cubic root of 16661700 is about 255.4111015869.

The spelling of 16661700 in words is "sixteen million, six hundred sixty-one thousand, seven hundred".