261100055 has 4 divisors (see below), whose sum is σ = 313320072. Its totient is φ = 208880040.

The previous prime is 261100039. The next prime is 261100097. The reversal of 261100055 is 550001162.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 261100055 - 2⁴ = 261100039 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 26110001 + ... + 26110010.

It is an arithmetic number, because the mean of its divisors is an integer number (78330018).

Almost surely, 2^261100055 is an apocalyptic number.

261100055 is a deficient number, since it is larger than the sum of its proper divisors (52220017).

261100055 is an equidigital number, since it uses as much as digits as its factorization.

261100055 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 52220016.

The product of its (nonzero) digits is 300, while the sum is 20.

The square root of 261100055 is about 16158.5907491959. The cubic root of 261100055 is about 639.1493051324.

The spelling of 261100055 in words is "two hundred sixty-one million, one hundred thousand, fifty-five".