15642 has 24 divisors (see below), whose sum is σ = 37440. Its totient is φ = 4680.

The previous prime is 15641. The next prime is 15643. The reversal of 15642 is 24651.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (15641) and next prime (15643).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is an Ulam number.

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 15642.

It is not an unprimeable number, because it can be changed into a prime (15641) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 159 + ... + 237.

It is an arithmetic number, because the mean of its divisors is an integer number (1560).

15642 is a Friedman number, since it can be written as 5^6+2^4+1, using all its digits and the basic arithmetic operations.

It is a practical number, because each smaller number is the sum of distinct divisors of 15642, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (18720).

15642 is an abundant number, since it is smaller than the sum of its proper divisors (21798).

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

15642 is a wasteful number, since it uses less digits than its factorization.

15642 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 98 (or 95 counting only the distinct ones).

The product of its digits is 240, while the sum is 18.

The square root of 15642 is about 125.0679815141. The cubic root of 15642 is about 25.0090633805.

Subtracting 15642 from its reverse (24651), we obtain a palindrome (9009).

The spelling of 15642 in words is "fifteen thousand, six hundred forty-two".