20840724 has 36 divisors (see below), whose sum is σ = 53909856. Its totient is φ = 6784848.

The previous prime is 20840717. The next prime is 20840761. The reversal of 20840724 is 42704802.

It is a tau number, because it is divible by the number of its divisors (36).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 5184 + ... + 8279.

It is an arithmetic number, because the mean of its divisors is an integer number (1497496).

Almost surely, 2^20840724 is an apocalyptic number.

It is an amenable number.

20840724 is an abundant number, since it is smaller than the sum of its proper divisors (33069132).

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

20840724 is a wasteful number, since it uses less digits than its factorization.

20840724 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13516 (or 13511 counting only the distinct ones).

The product of its (nonzero) digits is 3584, while the sum is 27.

The square root of 20840724 is about 4565.1641810564. The cubic root of 20840724 is about 275.1931381526.

The spelling of 20840724 in words is "twenty million, eight hundred forty thousand, seven hundred twenty-four".