261554037772611 has 16 divisors (see below), whose sum is σ = 369640222822944. Its totient is φ = 163940131375104.

The previous prime is 261554037772609. The next prime is 261554037772693. The reversal of 261554037772611 is 116277730455162.

261554037772611 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 261554037772611 - 2¹ = 261554037772609 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261554037777611) 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, 2690670466 + ... + 2690767671.

It is an arithmetic number, because the mean of its divisors is an integer number (23102513926434).

Almost surely, 2^{261554037772611} is an apocalyptic number.

261554037772611 is a deficient number, since it is larger than the sum of its proper divisors (108086185050333).

261554037772611 is a wasteful number, since it uses less digits than its factorization.

261554037772611 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5381439110.

The product of its (nonzero) digits is 14817600, while the sum is 57.

The spelling of 261554037772611 in words is "two hundred sixty-one trillion, five hundred fifty-four billion, thirty-seven million, seven hundred seventy-two thousand, six hundred eleven".