20500537 has 4 divisors (see below), whose sum is σ = 20514340. Its totient is φ = 20486736.

The previous prime is 20500531. The next prime is 20500541. The reversal of 20500537 is 73500502.

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

It can be written as a sum of positive squares in 2 ways, for example, as 16128256 + 4372281 = 4016^2 + 2091^2 .

It is a cyclic number.

It is not a de Polignac number, because 20500537 - 2²³ = 12111929 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20500531) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 4362 + ... + 7747.

It is an arithmetic number, because the mean of its divisors is an integer number (5128585).

Almost surely, 2^20500537 is an apocalyptic number.

It is an amenable number.

20500537 is a deficient number, since it is larger than the sum of its proper divisors (13803).

20500537 is a wasteful number, since it uses less digits than its factorization.

20500537 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13802.

The product of its (nonzero) digits is 1050, while the sum is 22.

The square root of 20500537 is about 4527.7518704099. The cubic root of 20500537 is about 273.6875734580.

The spelling of 20500537 in words is "twenty million, five hundred thousand, five hundred thirty-seven".