2581261321 has 4 divisors (see below), whose sum is σ = 2717117200. Its totient is φ = 2445405444.

The previous prime is 2581261307. The next prime is 2581261367. The reversal of 2581261321 is 1231621852.

2581261321 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2581261321 - 2⁹ = 2581260809 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2581261381) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 67927911 + ... + 67927948.

It is an arithmetic number, because the mean of its divisors is an integer number (679279300).

Almost surely, 2^2581261321 is an apocalyptic number.

It is an amenable number.

2581261321 is a deficient number, since it is larger than the sum of its proper divisors (135855879).

2581261321 is a wasteful number, since it uses less digits than its factorization.

2581261321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 135855878.

The product of its digits is 5760, while the sum is 31.

The square root of 2581261321 is about 50806.1149961301. The cubic root of 2581261321 is about 1371.7574407151.

The spelling of 2581261321 in words is "two billion, five hundred eighty-one million, two hundred sixty-one thousand, three hundred twenty-one".