15997530 has 32 divisors (see below), whose sum is σ = 38525184. Its totient is φ = 4251456.

The previous prime is 15997517. The next prime is 15997543. The reversal of 15997530 is 3579951.

15997530 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (15997517) and next prime (15997543).

It is a super-2 number, since 2×15997530² = 511841932201800, which contains 22 as substring.

It is a Smith number, since the sum of its digits (39) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 10284 + ... + 11736.

It is an arithmetic number, because the mean of its divisors is an integer number (1203912).

Almost surely, 2^15997530 is an apocalyptic number.

15997530 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

15997530 is an abundant number, since it is smaller than the sum of its proper divisors (22527654).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

15997530 is a wasteful number, since it uses less digits than its factorization.

15997530 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1830.

The product of its (nonzero) digits is 42525, while the sum is 39.

The square root of 15997530 is about 3999.6912380833. The cubic root of 15997530 is about 251.9712426242.

The spelling of 15997530 in words is "fifteen million, nine hundred ninety-seven thousand, five hundred thirty".