15947891 has 4 divisors (see below), whose sum is σ = 15963984. Its totient is φ = 15931800.

The previous prime is 15947843. The next prime is 15947909. The reversal of 15947891 is 19874951.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 19874951 = 109 ⋅182339.

It is a cyclic number.

It is not a de Polignac number, because 15947891 - 2¹⁴ = 15931507 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (15947801) 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, 6455 + ... + 8576.

It is an arithmetic number, because the mean of its divisors is an integer number (3990996).

Almost surely, 2^15947891 is an apocalyptic number.

15947891 is a deficient number, since it is larger than the sum of its proper divisors (16093).

15947891 is a wasteful number, since it uses less digits than its factorization.

15947891 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 16092.

The product of its digits is 90720, while the sum is 44.

The square root of 15947891 is about 3993.4810629324. The cubic root of 15947891 is about 251.7103573596.

The spelling of 15947891 in words is "fifteen million, nine hundred forty-seven thousand, eight hundred ninety-one".