261146550625 has 15 divisors (see below), whose sum is σ = 326344694863. Its totient is φ = 208907020000.

The previous prime is 261146550569. The next prime is 261146550631. The reversal of 261146550625 is 526055641162.

The square root of 261146550625 is 511025.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 7 ways, for example, as 106401873249 + 154744677376 = 326193^2 + 393376^2 .

It is a de Polignac number, because none of the positive numbers 2^k-261146550625 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 14 ways as a sum of consecutive naturals, for example, 12765405 + ... + 12785845.

Almost surely, 2^261146550625 is an apocalyptic number.

261146550625 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

261146550625 is the 511025-th square number.

261146550625 is the 255513-rd centered octagonal number.

It is an amenable number.

261146550625 is a deficient number, since it is larger than the sum of its proper divisors (65198144238).

261146550625 is an frugal number, since it uses more digits than its factorization.

261146550625 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40902 (or 20446 counting only the distinct ones).

The product of its (nonzero) digits is 432000, while the sum is 43.

The spelling of 261146550625 in words is "two hundred sixty-one billion, one hundred forty-six million, five hundred fifty thousand, six hundred twenty-five".