20321253523 has 4 divisors (see below), whose sum is σ = 20530751080. Its totient is φ = 20111755968.

The previous prime is 20321253509. The next prime is 20321253529. The reversal of 20321253523 is 32535212302.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 32535212302 = 2 ⋅16267606151.

It is a cyclic number.

It is not a de Polignac number, because 20321253523 - 2⁹ = 20321253011 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 20321253491 and 20321253500.

It is not an unprimeable number, because it can be changed into a prime (20321253529) 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, 104748633 + ... + 104748826.

It is an arithmetic number, because the mean of its divisors is an integer number (5132687770).

Almost surely, 2^20321253523 is an apocalyptic number.

20321253523 is a deficient number, since it is larger than the sum of its proper divisors (209497557).

20321253523 is an equidigital number, since it uses as much as digits as its factorization.

20321253523 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 209497556.

The product of its (nonzero) digits is 10800, while the sum is 28.

Adding to 20321253523 its reverse (32535212302), we get a palindrome (52856465825).

The spelling of 20321253523 in words is "twenty billion, three hundred twenty-one million, two hundred fifty-three thousand, five hundred twenty-three".