15978943 has 6 divisors (see below), whose sum is σ = 16864584. Its totient is φ = 15137604.

The previous prime is 15978923. The next prime is 15978967. The reversal of 15978943 is 34987951.

It is a happy number.

It is a de Polignac number, because none of the positive numbers 2^k-15978943 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 15978893 and 15978902.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15978923) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 21771 + ... + 22492.

It is an arithmetic number, because the mean of its divisors is an integer number (2810764).

Almost surely, 2^15978943 is an apocalyptic number.

15978943 is a deficient number, since it is larger than the sum of its proper divisors (885641).

15978943 is an equidigital number, since it uses as much as digits as its factorization.

15978943 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 44301 (or 44282 counting only the distinct ones).

The product of its digits is 272160, while the sum is 46.

The square root of 15978943 is about 3997.3670084194. The cubic root of 15978943 is about 251.8736191268.

The spelling of 15978943 in words is "fifteen million, nine hundred seventy-eight thousand, nine hundred forty-three".