20616523 has 4 divisors (see below), whose sum is σ = 21005568. Its totient is φ = 20227480.

The previous prime is 20616521. The next prime is 20616559. The reversal of 20616523 is 32561602.

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 20616523 - 2¹ = 20616521 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (20616521) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 194443 + ... + 194548.

It is an arithmetic number, because the mean of its divisors is an integer number (5251392).

Almost surely, 2^20616523 is an apocalyptic number.

20616523 is a deficient number, since it is larger than the sum of its proper divisors (389045).

20616523 is an equidigital number, since it uses as much as digits as its factorization.

20616523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 389044.

The product of its (nonzero) digits is 2160, while the sum is 25.

The square root of 20616523 is about 4540.5421482462. The cubic root of 20616523 is about 274.2027509942.

The spelling of 20616523 in words is "twenty million, six hundred sixteen thousand, five hundred twenty-three".