20669766 has 16 divisors (see below), whose sum is σ = 44519664. Its totient is φ = 6359904.

The previous prime is 20669729. The next prime is 20669767. The reversal of 20669766 is 66796602.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20669767) by changing a digit.

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 7 ways as a sum of consecutive naturals, for example, 132421 + ... + 132576.

It is an arithmetic number, because the mean of its divisors is an integer number (2782479).

Almost surely, 2^20669766 is an apocalyptic number.

20669766 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

20669766 is an abundant number, since it is smaller than the sum of its proper divisors (23849898).

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

20669766 is a wasteful number, since it uses less digits than its factorization.

20669766 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 265015.

The product of its (nonzero) digits is 163296, while the sum is 42.

The square root of 20669766 is about 4546.4014341015. The cubic root of 20669766 is about 274.4385946303.

The spelling of 20669766 in words is "twenty million, six hundred sixty-nine thousand, seven hundred sixty-six".