15981332891 has 8 divisors (see below), whose sum is σ = 16261881840. Its totient is φ = 15701106688.

The previous prime is 15981332837. The next prime is 15981332893. The reversal of 15981332891 is 19823318951.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-15981332891 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15981332893) 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, 20315 + ... + 179931.

It is an arithmetic number, because the mean of its divisors is an integer number (2032735230).

Almost surely, 2^15981332891 is an apocalyptic number.

15981332891 is a deficient number, since it is larger than the sum of its proper divisors (280548949).

15981332891 is a wasteful number, since it uses less digits than its factorization.

15981332891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 161373.

The product of its digits is 466560, while the sum is 50.

The spelling of 15981332891 in words is "fifteen billion, nine hundred eighty-one million, three hundred thirty-two thousand, eight hundred ninety-one".