15997550 has 24 divisors (see below), whose sum is σ = 30718272. Its totient is φ = 6192000.

The previous prime is 15997549. The next prime is 15997559. The reversal of 15997550 is 5579951.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 15997498 and 15997507.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (15997559) 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 11 ways as a sum of consecutive naturals, for example, 3611 + ... + 6710.

It is an arithmetic number, because the mean of its divisors is an integer number (1279928).

Almost surely, 2^15997550 is an apocalyptic number.

15997550 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

15997550 is a deficient number, since it is larger than the sum of its proper divisors (14720722).

15997550 is a wasteful number, since it uses less digits than its factorization.

15997550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10364 (or 10359 counting only the distinct ones).

The product of its (nonzero) digits is 70875, while the sum is 41.

The square root of 15997550 is about 3999.6937382755. The cubic root of 15997550 is about 251.9713476284.

The spelling of 15997550 in words is "fifteen million, nine hundred ninety-seven thousand, five hundred fifty".