1261686255 has 8 divisors (see below), whose sum is σ = 2018698032. Its totient is φ = 672899328.

The previous prime is 1261686221. The next prime is 1261686269. The reversal of 1261686255 is 5526861621.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 1261686255 - 2¹³ = 1261678063 is a prime.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 42056194 + ... + 42056223.

It is an arithmetic number, because the mean of its divisors is an integer number (252337254).

Almost surely, 2^1261686255 is an apocalyptic number.

1261686255 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

1261686255 is a deficient number, since it is larger than the sum of its proper divisors (757011777).

1261686255 is an equidigital number, since it uses as much as digits as its factorization.

1261686255 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 84112425.

The product of its digits is 172800, while the sum is 42.

The square root of 1261686255 is about 35520.2231834205. The cubic root of 1261686255 is about 1080.5639073298.

The spelling of 1261686255 in words is "one billion, two hundred sixty-one million, six hundred eighty-six thousand, two hundred fifty-five".