21031302320 has 160 divisors (see below), whose sum is σ = 56527632000. Its totient is φ = 7128096768.

The previous prime is 21031302319. The next prime is 21031302337. The reversal of 21031302320 is 2320313012.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 22444892 + ... + 22445828.

It is an arithmetic number, because the mean of its divisors is an integer number (353297700).

Almost surely, 2^21031302320 is an apocalyptic number.

21031302320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21031302320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (28263816000).

21031302320 is an abundant number, since it is smaller than the sum of its proper divisors (35496329680).

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

21031302320 is a wasteful number, since it uses less digits than its factorization.

21031302320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1375 (or 1369 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 17.

Adding to 21031302320 its reverse (2320313012), we get a palindrome (23351615332).

The spelling of 21031302320 in words is "twenty-one billion, thirty-one million, three hundred two thousand, three hundred twenty".