2561905125 has 64 divisors (see below), whose sum is σ = 5101125120. Its totient is φ = 1261224000.

The previous prime is 2561905111. The next prime is 2561905169. The reversal of 2561905125 is 5215091652.

2561905125 is a `hidden beast` number, since 2 + 56 + 1 + 90 + 512 + 5 = 666.

2561905125 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 2561905125 - 2¹⁰ = 2561904101 is a prime.

It is a nialpdrome in base 15.

It is a self number, because there is not a number n which added to its sum of digits gives 2561905125.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 14680 + ... + 73070.

It is an arithmetic number, because the mean of its divisors is an integer number (79705080).

Almost surely, 2^2561905125 is an apocalyptic number.

2561905125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

2561905125 is a deficient number, since it is larger than the sum of its proper divisors (2539219995).

2561905125 is a wasteful number, since it uses less digits than its factorization.

2561905125 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 58428 (or 58412 counting only the distinct ones).

The product of its (nonzero) digits is 27000, while the sum is 36.

The square root of 2561905125 is about 50615.2657308050. The cubic root of 2561905125 is about 1368.3200188142.

Adding to 2561905125 its reverse (5215091652), we get a palindrome (7776996777).

The spelling of 2561905125 in words is "two billion, five hundred sixty-one million, nine hundred five thousand, one hundred twenty-five".