261021085461 has 6 divisors (see below), whose sum is σ = 377030456790. Its totient is φ = 174014056968.

The previous prime is 261021085459. The next prime is 261021085463. The reversal of 261021085461 is 164580120162.

It is a happy number.

261021085461 is a `hidden beast` number, since 2 + 6 + 1 + 0 + 2 + 108 + 546 + 1 = 666.

261021085461 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is an interprime number because it is at equal distance from previous prime (261021085459) and next prime (261021085463).

It can be written as a sum of positive squares in only one way, i.e., 204388984836 + 56632100625 = 452094^2 + 237975^2 .

It is not a de Polignac number, because 261021085461 - 2¹ = 261021085459 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (261021085463) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 14501171406 + ... + 14501171423.

It is an arithmetic number, because the mean of its divisors is an integer number (62838409465).

Almost surely, 2^261021085461 is an apocalyptic number.

It is an amenable number.

261021085461 is a deficient number, since it is larger than the sum of its proper divisors (116009371329).

261021085461 is a wasteful number, since it uses less digits than its factorization.

261021085461 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 29002342835 (or 29002342832 counting only the distinct ones).

The product of its (nonzero) digits is 23040, while the sum is 36.

The spelling of 261021085461 in words is "two hundred sixty-one billion, twenty-one million, eighty-five thousand, four hundred sixty-one".