20730724 has 18 divisors (see below), whose sum is σ = 42202230. Its totient is φ = 8884512.

The previous prime is 20730719. The next prime is 20730733. The reversal of 20730724 is 42703702.

It can be written as a sum of positive squares in only one way, i.e., 20702500 + 28224 = 4550^2 + 168^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 52689 + ... + 53080.

Almost surely, 2^20730724 is an apocalyptic number.

It is an amenable number.

20730724 is an abundant number, since it is smaller than the sum of its proper divisors (21471506).

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

20730724 is a wasteful number, since it uses less digits than its factorization.

20730724 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105787 (or 105778 counting only the distinct ones).

The product of its (nonzero) digits is 2352, while the sum is 25.

The square root of 20730724 is about 4553.1004820891. The cubic root of 20730724 is about 274.7081156486.

The spelling of 20730724 in words is "twenty million, seven hundred thirty thousand, seven hundred twenty-four".