15978241 has 4 divisors (see below), whose sum is σ = 16349872. Its totient is φ = 15606612.

The previous prime is 15978239. The next prime is 15978253. The reversal of 15978241 is 14287951.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also an emirpimes, since its reverse is a distinct semiprime: 14287951 = 67 ⋅213253.

It is a cyclic number.

It is not a de Polignac number, because 15978241 - 2¹ = 15978239 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 15978241.

It is not an unprimeable number, because it can be changed into a prime (15978211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 185751 + ... + 185836.

It is an arithmetic number, because the mean of its divisors is an integer number (4087468).

Almost surely, 2^15978241 is an apocalyptic number.

It is an amenable number.

15978241 is a deficient number, since it is larger than the sum of its proper divisors (371631).

15978241 is an equidigital number, since it uses as much as digits as its factorization.

15978241 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 371630.

The product of its digits is 20160, while the sum is 37.

The square root of 15978241 is about 3997.2791996557. The cubic root of 15978241 is about 251.8699305668.

It can be divided in two parts, 159 and 78241, that added together give a square (78400 = 280²).

The spelling of 15978241 in words is "fifteen million, nine hundred seventy-eight thousand, two hundred forty-one".