15994969117 has 4 divisors (see below), whose sum is σ = 16001803996. Its totient is φ = 15988134240.

The previous prime is 15994969103. The next prime is 15994969147. The reversal of 15994969117 is 71196949951.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 71196949951 = 3739 ⋅19041709.

It can be written as a sum of positive squares in 2 ways, for example, as 4363130916 + 11631838201 = 66054^2 + 107851^2 .

It is a cyclic number.

It is not a de Polignac number, because 15994969117 - 2¹¹ = 15994967069 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15994969147) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3413928 + ... + 3418609.

It is an arithmetic number, because the mean of its divisors is an integer number (4000450999).

Almost surely, 2^15994969117 is an apocalyptic number.

It is an amenable number.

15994969117 is a deficient number, since it is larger than the sum of its proper divisors (6834879).

15994969117 is an equidigital number, since it uses as much as digits as its factorization.

15994969117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 6834878.

The product of its digits is 5511240, while the sum is 61.

The spelling of 15994969117 in words is "fifteen billion, nine hundred ninety-four million, nine hundred sixty-nine thousand, one hundred seventeen".