20842666 has 8 divisors (see below), whose sum is σ = 33668964. Its totient is φ = 9619680.

The previous prime is 20842631. The next prime is 20842673. The reversal of 20842666 is 66624802.

It can be written as a sum of positive squares in 2 ways, for example, as 20439441 + 403225 = 4521^2 + 635^2 .

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

It is an unprimeable number.

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, 400795 + ... + 400846.

Almost surely, 2^20842666 is an apocalyptic number.

20842666 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20842666 is a deficient number, since it is larger than the sum of its proper divisors (12826298).

20842666 is a wasteful number, since it uses less digits than its factorization.

20842666 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 801656.

The product of its (nonzero) digits is 27648, while the sum is 34.

The square root of 20842666 is about 4565.3768738189. The cubic root of 20842666 is about 275.2016856559.

The spelling of 20842666 in words is "twenty million, eight hundred forty-two thousand, six hundred sixty-six".