20521245304 has 64 divisors (see below), whose sum is σ = 44634240000. Its totient is φ = 8663020800.

The previous prime is 20521245301. The next prime is 20521245307. The reversal of 20521245304 is 40354212502.

It is an interprime number because it is at equal distance from previous prime (20521245301) and next prime (20521245307).

It is a super-2 number, since 2×20521245304² (a number of 21 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (28).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20521245301) 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, 6841197 + ... + 6844195.

It is an arithmetic number, because the mean of its divisors is an integer number (697410000).

Almost surely, 2^20521245304 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 20521245304, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (22317120000).

20521245304 is an abundant number, since it is smaller than the sum of its proper divisors (24112994696).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20521245304 is a wasteful number, since it uses less digits than its factorization.

20521245304 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4804 (or 4800 counting only the distinct ones).

The product of its (nonzero) digits is 9600, while the sum is 28.

Adding to 20521245304 its reverse (40354212502), we get a palindrome (60875457806).

The spelling of 20521245304 in words is "twenty billion, five hundred twenty-one million, two hundred forty-five thousand, three hundred four".