2581721875 has 12 divisors (see below), whose sum is σ = 3226949712. Its totient is φ = 2065375000.

The previous prime is 2581721837. The next prime is 2581721911. The reversal of 2581721875 is 5781271852.

It is not a de Polignac number, because 2581721875 - 2²⁹ = 2044850963 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 409951 + ... + 416200.

It is an arithmetic number, because the mean of its divisors is an integer number (268912476).

Almost surely, 2^2581721875 is an apocalyptic number.

2581721875 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

2581721875 is a deficient number, since it is larger than the sum of its proper divisors (645227837).

2581721875 is an frugal number, since it uses more digits than its factorization.

2581721875 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 826176 (or 826156 counting only the distinct ones).

The product of its digits is 313600, while the sum is 46.

The square root of 2581721875 is about 50810.6472601954. The cubic root of 2581721875 is about 1371.8390197996.

The spelling of 2581721875 in words is "two billion, five hundred eighty-one million, seven hundred twenty-one thousand, eight hundred seventy-five".