15997329 has 6 divisors (see below), whose sum is σ = 23107266. Its totient is φ = 10664880.

The previous prime is 15997313. The next prime is 15997367. The reversal of 15997329 is 92379951.

It is a happy number.

It can be written as a sum of positive squares in only one way, i.e., 11068929 + 4928400 = 3327^2 + 2220^2 .

It is not a de Polignac number, because 15997329 - 2⁴ = 15997313 is a prime.

It is not an unprimeable number, because it can be changed into a prime (15997369) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 888732 + ... + 888749.

It is an arithmetic number, because the mean of its divisors is an integer number (3851211).

Almost surely, 2^15997329 is an apocalyptic number.

It is an amenable number.

15997329 is a deficient number, since it is larger than the sum of its proper divisors (7109937).

15997329 is a wasteful number, since it uses less digits than its factorization.

15997329 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1777487 (or 1777484 counting only the distinct ones).

The product of its digits is 153090, while the sum is 45.

The square root of 15997329 is about 3999.6661110648. Note that the first 3 decimals coincide. The cubic root of 15997329 is about 251.9701873273.

The spelling of 15997329 in words is "fifteen million, nine hundred ninety-seven thousand, three hundred twenty-nine".