16720447221320 has 16 divisors (see below), whose sum is σ = 37621006248060. Its totient is φ = 6688178888512.

The previous prime is 16720447221241. The next prime is 16720447221347. The reversal of 16720447221320 is 2312274402761.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 13625739985636 + 3094707235684 = 3691306^2 + 1759178^2 .

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 209005590227 + ... + 209005590306.

Almost surely, 2^{16720447221320} is an apocalyptic number.

16720447221320 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

16720447221320 is an abundant number, since it is smaller than the sum of its proper divisors (20900559026740).

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

16720447221320 is a wasteful number, since it uses less digits than its factorization.

16720447221320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 418011180544 (or 418011180540 counting only the distinct ones).

The product of its (nonzero) digits is 225792, while the sum is 41.

The spelling of 16720447221320 in words is "sixteen trillion, seven hundred twenty billion, four hundred forty-seven million, two hundred twenty-one thousand, three hundred twenty".