16721161136530 has 16 divisors (see below), whose sum is σ = 30098335515480. Its totient is φ = 6688409905792.

The previous prime is 16721161136447. The next prime is 16721161136539. The reversal of 16721161136530 is 3563116112761.

It can be written as a sum of positive squares in 4 ways, for example, as 16621757766441 + 99403370089 = 4076979^2 + 315283^2 .

It is not an unprimeable number, because it can be changed into a prime (16721161136539) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5519365 + ... + 7994104.

Almost surely, 2^{16721161136530} is an apocalyptic number.

16721161136530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

16721161136530 is a deficient number, since it is larger than the sum of its proper divisors (13377174378950).

16721161136530 is a wasteful number, since it uses less digits than its factorization.

16721161136530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13637213.

The product of its (nonzero) digits is 136080, while the sum is 43.

The spelling of 16721161136530 in words is "sixteen trillion, seven hundred twenty-one billion, one hundred sixty-one million, one hundred thirty-six thousand, five hundred thirty".