261328780275 has 48 divisors (see below), whose sum is σ = 434401208448. Its totient is φ = 138622176000.

The previous prime is 261328780267. The next prime is 261328780291. The reversal of 261328780275 is 572087823162.

It is not a de Polignac number, because 261328780275 - 2³ = 261328780267 is a prime.

It is a hoax number, since the sum of its digits (51) coincides with the sum of the digits of its distinct prime factors.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 28274655 + ... + 28283895.

It is an arithmetic number, because the mean of its divisors is an integer number (9050025176).

Almost surely, 2^261328780275 is an apocalyptic number.

261328780275 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

261328780275 is a deficient number, since it is larger than the sum of its proper divisors (173072428173).

261328780275 is a wasteful number, since it uses less digits than its factorization.

261328780275 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11252 (or 11247 counting only the distinct ones).

The product of its (nonzero) digits is 2257920, while the sum is 51.

The spelling of 261328780275 in words is "two hundred sixty-one billion, three hundred twenty-eight million, seven hundred eighty thousand, two hundred seventy-five".