20729824 has 24 divisors (see below), whose sum is σ = 42130368. Its totient is φ = 10030080.

The previous prime is 20729789. The next prime is 20729861. The reversal of 20729824 is 42892702.

It is a self number, because there is not a number n which added to its sum of digits gives 20729824.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 9457 + ... + 11440.

It is an arithmetic number, because the mean of its divisors is an integer number (1755432).

Almost surely, 2^20729824 is an apocalyptic number.

It is an amenable number.

20729824 is an abundant number, since it is smaller than the sum of its proper divisors (21400544).

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

20729824 is a wasteful number, since it uses less digits than its factorization.

20729824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20938 (or 20930 counting only the distinct ones).

The product of its (nonzero) digits is 16128, while the sum is 34.

The square root of 20729824 is about 4553.0016472652. The cubic root of 20729824 is about 274.7041402145.

It can be divided in two parts, 2072982 and 4, that multiplied together give a palindrome (8291928).

The spelling of 20729824 in words is "twenty million, seven hundred twenty-nine thousand, eight hundred twenty-four".