261479555 has 16 divisors (see below), whose sum is σ = 325237440. Its totient is φ = 201647232.

The previous prime is 261479549. The next prime is 261479557. The reversal of 261479555 is 555974162.

It is a happy number.

It is a cyclic number.

It is not a de Polignac number, because 261479555 - 2¹⁴ = 261463171 is a prime.

It is not an unprimeable number, because it can be changed into a prime (261479557) 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, 13682 + ... + 26648.

It is an arithmetic number, because the mean of its divisors is an integer number (20327340).

Almost surely, 2^261479555 is an apocalyptic number.

261479555 is a deficient number, since it is larger than the sum of its proper divisors (63757885).

261479555 is a wasteful number, since it uses less digits than its factorization.

261479555 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 13118.

The product of its digits is 378000, while the sum is 44.

The square root of 261479555 is about 16170.3294647945. The cubic root of 261479555 is about 639.4588157782.

The spelling of 261479555 in words is "two hundred sixty-one million, four hundred seventy-nine thousand, five hundred fifty-five".