13318991521 has 16 divisors (see below), whose sum is σ = 14888966400. Its totient is φ = 11812013200.

The previous prime is 13318991519. The next prime is 13318991533. The reversal of 13318991521 is 12519981331.

It is a cyclic number.

It is not a de Polignac number, because 13318991521 - 2¹ = 13318991519 is a prime.

It is not an unprimeable number, because it can be changed into a prime (13318991551) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 6690 + ... + 163348.

It is an arithmetic number, because the mean of its divisors is an integer number (930560400).

Almost surely, 2^13318991521 is an apocalyptic number.

13318991521 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

13318991521 is a deficient number, since it is larger than the sum of its proper divisors (1569974879).

13318991521 is a wasteful number, since it uses less digits than its factorization.

13318991521 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 156860.

The product of its digits is 58320, while the sum is 43.

The spelling of 13318991521 in words is "thirteen billion, three hundred eighteen million, nine hundred ninety-one thousand, five hundred twenty-one".