2605721216 has 96 divisors (see below), whose sum is σ = 6186502980. Its totient is φ = 1089392640.

The previous prime is 2605721177. The next prime is 2605721269. The reversal of 2605721216 is 6121275062.

It can be written as a sum of positive squares in 2 ways, for example, as 2568462400 + 37258816 = 50680^2 + 6104^2 .

It is a Harshad number since it is a multiple of its sum of digits (32).

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 252086 + ... + 262218.

Almost surely, 2^2605721216 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 2605721216, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3093251490).

2605721216 is an abundant number, since it is smaller than the sum of its proper divisors (3580781764).

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

2605721216 is a wasteful number, since it uses less digits than its factorization.

2605721216 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10202 (or 10183 counting only the distinct ones).

The product of its (nonzero) digits is 10080, while the sum is 32.

The square root of 2605721216 is about 51046.2654461617. The cubic root of 2605721216 is about 1376.0767263868.

Adding to 2605721216 its reverse (6121275062), we get a palindrome (8726996278).

The spelling of 2605721216 in words is "two billion, six hundred five million, seven hundred twenty-one thousand, two hundred sixteen".