15601664 has 52 divisors (see below), whose sum is σ = 33714156. Its totient is φ = 7176192.

The previous prime is 15601661. The next prime is 15601667. The reversal of 15601664 is 46610651.

It is an interprime number because it is at equal distance from previous prime (15601661) and next prime (15601667).

It can be written as a sum of positive squares in 2 ways, for example, as 9048064 + 6553600 = 3008^2 + 2560^2 .

It is a tau number, because it is divible by the number of its divisors (52).

It is a nialpdrome in base 16.

It is not an unprimeable number, because it can be changed into a prime (15601661) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 53102 + ... + 53394.

Almost surely, 2^15601664 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 15601664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (16857078).

15601664 is an abundant number, since it is smaller than the sum of its proper divisors (18112492).

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

15601664 is an equidigital number, since it uses as much as digits as its factorization.

15601664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 330 (or 308 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 29.

The square root of 15601664 is about 3949.8941757976. The cubic root of 15601664 is about 249.8754793220.

The spelling of 15601664 in words is "fifteen million, six hundred one thousand, six hundred sixty-four".