20729886 has 32 divisors (see below), whose sum is σ = 43545600. Its totient is φ = 6570240.

The previous prime is 20729873. The next prime is 20729897. The reversal of 20729886 is 68892702.

It is a happy number.

It is a Curzon number.

It is a congruent number.

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 15 ways as a sum of consecutive naturals, for example, 10030 + ... + 11918.

It is an arithmetic number, because the mean of its divisors is an integer number (1360800).

Almost surely, 2^20729886 is an apocalyptic number.

20729886 is an abundant number, since it is smaller than the sum of its proper divisors (22815714).

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

20729886 is a wasteful number, since it uses less digits than its factorization.

20729886 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1984.

The product of its (nonzero) digits is 96768, while the sum is 42.

The square root of 20729886 is about 4553.0084559552. The cubic root of 20729886 is about 274.7044140814.

The spelling of 20729886 in words is "twenty million, seven hundred twenty-nine thousand, eight hundred eighty-six".