261133550 has 12 divisors (see below), whose sum is σ = 485708496. Its totient is φ = 104453400.

The previous prime is 261133529. The next prime is 261133567. The reversal of 261133550 is 55331162.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 2611286 + ... + 2611385.

It is an arithmetic number, because the mean of its divisors is an integer number (40475708).

Almost surely, 2^261133550 is an apocalyptic number.

261133550 is a deficient number, since it is larger than the sum of its proper divisors (224574946).

261133550 is a wasteful number, since it uses less digits than its factorization.

261133550 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5222683 (or 5222678 counting only the distinct ones).

The product of its (nonzero) digits is 2700, while the sum is 26.

The square root of 261133550 is about 16159.6271615406. The cubic root of 261133550 is about 639.1766348733.

The spelling of 261133550 in words is "two hundred sixty-one million, one hundred thirty-three thousand, five hundred fifty".