20716539 has 4 divisors (see below), whose sum is σ = 27622056. Its totient is φ = 13811024.

The previous prime is 20716483. The next prime is 20716541. The reversal of 20716539 is 93561702.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 20716539 - 2¹⁹ = 20192251 is a prime.

It is not an unprimeable number, because it can be changed into a prime (20716589) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3452754 + ... + 3452759.

It is an arithmetic number, because the mean of its divisors is an integer number (6905514).

Almost surely, 2^20716539 is an apocalyptic number.

20716539 is a deficient number, since it is larger than the sum of its proper divisors (6905517).

20716539 is an equidigital number, since it uses as much as digits as its factorization.

20716539 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6905516.

The product of its (nonzero) digits is 11340, while the sum is 33.

The square root of 20716539 is about 4551.5424857953. The cubic root of 20716539 is about 274.6454450003.

The spelling of 20716539 in words is "twenty million, seven hundred sixteen thousand, five hundred thirty-nine".