20000521 has 8 divisors (see below), whose sum is σ = 21502080. Its totient is φ = 18543888.

The previous prime is 20000507. The next prime is 20000531. The reversal of 20000521 is 12500002.

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

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20000521 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20000498 and 20000507.

It is not an unprimeable number, because it can be changed into a prime (20000531) 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 7 ways as a sum of consecutive naturals, for example, 10306 + ... + 12091.

It is an arithmetic number, because the mean of its divisors is an integer number (2687760).

Almost surely, 2^20000521 is an apocalyptic number.

It is an amenable number.

20000521 is a deficient number, since it is larger than the sum of its proper divisors (1501559).

20000521 is a wasteful number, since it uses less digits than its factorization.

20000521 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22463.

The product of its (nonzero) digits is 20, while the sum is 10.

The square root of 20000521 is about 4472.1942041910. The cubic root of 20000521 is about 271.4441186583. Note that the first 3 decimals are identical.

Adding to 20000521 its reverse (12500002), we get a palindrome (32500523).

The spelling of 20000521 in words is "twenty million, five hundred twenty-one", and thus it is an aban number.