21011350320 has 160 divisors (see below), whose sum is σ = 73049610240. Its totient is φ = 5550600960.

The previous prime is 21011350307. The next prime is 21011350331. The reversal of 21011350320 is 2305311012.

21011350320 is a `hidden beast` number, since 210 + 1 + 135 + 0 + 320 = 666.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 21011350293 and 21011350302.

It is an unprimeable number.

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 31 ways as a sum of consecutive naturals, for example, 185665 + ... + 276575.

It is an arithmetic number, because the mean of its divisors is an integer number (456560064).

Almost surely, 2^21011350320 is an apocalyptic number.

21011350320 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 21011350320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (36524805120).

21011350320 is an abundant number, since it is smaller than the sum of its proper divisors (52038259920).

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

21011350320 is a wasteful number, since it uses less digits than its factorization.

21011350320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 91040 (or 91028 counting only the distinct ones).

The product of its (nonzero) digits is 180, while the sum is 18.

Adding to 21011350320 its reverse (2305311012), we get a palindrome (23316661332).

The spelling of 21011350320 in words is "twenty-one billion, eleven million, three hundred fifty thousand, three hundred twenty".