15997685 has 16 divisors (see below), whose sum is σ = 21071232. Its totient is φ = 11563200.

The previous prime is 15997637. The next prime is 15997691. The reversal of 15997685 is 58679951.

It is a happy number.

It is not a de Polignac number, because 15997685 - 2⁶ = 15997621 is a prime.

It is a Duffinian number.

It is a congruent 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, 9152 + ... + 10758.

It is an arithmetic number, because the mean of its divisors is an integer number (1316952).

Almost surely, 2^15997685 is an apocalyptic number.

It is an amenable number.

15997685 is a deficient number, since it is larger than the sum of its proper divisors (5073547).

15997685 is a wasteful number, since it uses less digits than its factorization.

15997685 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1804.

The product of its digits is 680400, while the sum is 50.

The square root of 15997685 is about 3999.7106145320. The cubic root of 15997685 is about 251.9720564043.

It can be divided in two parts, 159976 and 85, that added together give a palindrome (160061).

The spelling of 15997685 in words is "fifteen million, nine hundred ninety-seven thousand, six hundred eighty-five".