20530745 has 8 divisors (see below), whose sum is σ = 25302984. Its totient is φ = 15980544.

The previous prime is 20530723. The next prime is 20530759. The reversal of 20530745 is 54703502.

It can be written as a sum of positive squares in 4 ways, for example, as 7513081 + 13017664 = 2741^2 + 3608^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 20530745 - 2¹⁶ = 20465209 is a prime.

It is a super-2 number, since 2×20530745² = 843022980510050, which contains 22 as substring.

It is a Duffinian number.

It is a Curzon number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 55304 + ... + 55673.

It is an arithmetic number, because the mean of its divisors is an integer number (3162873).

Almost surely, 2^20530745 is an apocalyptic number.

It is an amenable number.

20530745 is a deficient number, since it is larger than the sum of its proper divisors (4772239).

20530745 is a wasteful number, since it uses less digits than its factorization.

20530745 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 111019.

The product of its (nonzero) digits is 4200, while the sum is 26.

The square root of 20530745 is about 4531.0865142921. The cubic root of 20530745 is about 273.8219357388.

The spelling of 20530745 in words is "twenty million, five hundred thirty thousand, seven hundred forty-five".