16400666 has 8 divisors (see below), whose sum is σ = 24634260. Its totient is φ = 8189248.

The previous prime is 16400647. The next prime is 16400669. The reversal of 16400666 is 66600461.

It can be written as a sum of positive squares in 2 ways, for example, as 15642025 + 758641 = 3955^2 + 871^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is not an unprimeable number, because it can be changed into a prime (16400669) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3551 + ... + 6738.

Almost surely, 2^16400666 is an apocalyptic number.

16400666 is a deficient number, since it is larger than the sum of its proper divisors (8233594).

16400666 is a wasteful number, since it uses less digits than its factorization.

16400666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11088.

The product of its (nonzero) digits is 5184, while the sum is 29.

The square root of 16400666 is about 4049.7735739174. The cubic root of 16400666 is about 254.0702577051.

The spelling of 16400666 in words is "sixteen million, four hundred thousand, six hundred sixty-six".