261415204305 has 16 divisors (see below), whose sum is σ = 418325259840. Its totient is φ = 139401131328.

The previous prime is 261415204283. The next prime is 261415204307. The reversal of 261415204305 is 503402514162.

It is not a de Polignac number, because 261415204305 - 2¹⁰ = 261415203281 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261415204307) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1162750 + ... + 1369239.

It is an arithmetic number, because the mean of its divisors is an integer number (26145328740).

Almost surely, 2^261415204305 is an apocalyptic number.

It is an amenable number.

261415204305 is a deficient number, since it is larger than the sum of its proper divisors (156910055535).

261415204305 is a wasteful number, since it uses less digits than its factorization.

261415204305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2538880.

The product of its (nonzero) digits is 28800, while the sum is 33.

Adding to 261415204305 its reverse (503402514162), we get a palindrome (764817718467).

The spelling of 261415204305 in words is "two hundred sixty-one billion, four hundred fifteen million, two hundred four thousand, three hundred five".