20521323321 has 16 divisors (see below), whose sum is σ = 28249847808. Its totient is φ = 13242096000.

The previous prime is 20521323259. The next prime is 20521323353. The reversal of 20521323321 is 12332312502.

It is a happy number.

It is not a de Polignac number, because 20521323321 - 2⁶ = 20521323257 is a prime.

It is a super-2 number, since 2×20521323321² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 20521323291 and 20521323300.

It is not an unprimeable number, because it can be changed into a prime (20521323391) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 641230 + ... + 672471.

It is an arithmetic number, because the mean of its divisors is an integer number (1765615488).

Almost surely, 2^20521323321 is an apocalyptic number.

It is an amenable number.

20521323321 is a deficient number, since it is larger than the sum of its proper divisors (7728524487).

20521323321 is a wasteful number, since it uses less digits than its factorization.

20521323321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1313872.

The product of its (nonzero) digits is 2160, while the sum is 24.

Adding to 20521323321 its reverse (12332312502), we get a palindrome (32853635823).

The spelling of 20521323321 in words is "twenty billion, five hundred twenty-one million, three hundred twenty-three thousand, three hundred twenty-one".