20213523 has 16 divisors (see below), whose sum is σ = 32668800. Its totient is φ = 12250440.

The previous prime is 20213503. The next prime is 20213563. The reversal of 20213523 is 32531202.

It is not a de Polignac number, because 20213523 - 2⁸ = 20213267 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20213496 and 20213505.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20213503) 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 15 ways as a sum of consecutive naturals, for example, 33733 + ... + 34326.

It is an arithmetic number, because the mean of its divisors is an integer number (2041800).

Almost surely, 2^20213523 is an apocalyptic number.

20213523 is a deficient number, since it is larger than the sum of its proper divisors (12455277).

20213523 is a wasteful number, since it uses less digits than its factorization.

20213523 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 68079 (or 68073 counting only the distinct ones).

The product of its (nonzero) digits is 360, while the sum is 18.

The square root of 20213523 is about 4495.9451731532. The cubic root of 20213523 is about 272.4043285617.

Adding to 20213523 its reverse (32531202), we get a palindrome (52744725).

It can be divided in two parts, 20213 and 523, that added together give a 4-th power (20736 = 12⁴).

The spelling of 20213523 in words is "twenty million, two hundred thirteen thousand, five hundred twenty-three".