2521664 has 42 divisors (see below), whose sum is σ = 5296662. Its totient is φ = 1190400.

The previous prime is 2521643. The next prime is 2521681. The reversal of 2521664 is 4661252.

It can be written as a sum of positive squares in only one way, i.e., 1537600 + 984064 = 1240^2 + 992^2 .

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 61484 + ... + 61524.

It is an arithmetic number, because the mean of its divisors is an integer number (126111).

2^2521664 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 2521664, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2648331).

2521664 is an abundant number, since it is smaller than the sum of its proper divisors (2774998).

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

2521664 is an equidigital number, since it uses as much as digits as its factorization.

2521664 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 115 (or 74 counting only the distinct ones).

The product of its digits is 2880, while the sum is 26.

The square root of 2521664 is about 1587.9748108833. The cubic root of 2521664 is about 136.1117881343. Note that the first 3 decimals are identical.

The spelling of 2521664 in words is "two million, five hundred twenty-one thousand, six hundred sixty-four".