13985191081 has 3 divisors (see below), whose sum is σ = 13985309341. Its totient is φ = 13985072822.

The previous prime is 13985191067. The next prime is 13985191093. The reversal of 13985191081 is 18019158931.

The square root of 13985191081 is 118259.

It is a perfect power (a square), and thus also a powerful number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 18019158931 = 14197 ⋅1269223.

It is a de Polignac number, because none of the positive numbers 2^k-13985191081 is a prime.

It is a super-2 number, since 2×13985191081² (a number of 21 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13985191981) by changing a digit.

It is a polite number, since it can be written in 2 ways as a sum of consecutive naturals, for example, 59130 + ... + 177388.

Almost surely, 2^13985191081 is an apocalyptic number.

13985191081 is the 118259-th square number.

13985191081 is the 59130-th centered octagonal number.

It is an amenable number.

13985191081 is a deficient number, since it is larger than the sum of its proper divisors (118260).

13985191081 is an frugal number, since it uses more digits than its factorization.

13985191081 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 236518 (or 118259 counting only the distinct ones).

The product of its (nonzero) digits is 77760, while the sum is 46.

The spelling of 13985191081 in words is "thirteen billion, nine hundred eighty-five million, one hundred ninety-one thousand, eighty-one".