261771505475 has 6 divisors (see below), whose sum is σ = 324596666820. Its totient is φ = 209417204360.

The previous prime is 261771505417. The next prime is 261771505487. The reversal of 261771505475 is 574505177162.

It is a happy number.

It is not a de Polignac number, because 261771505475 - 2²² = 261767311171 is a prime.

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, 5235430085 + ... + 5235430134.

It is an arithmetic number, because the mean of its divisors is an integer number (54099444470).

Almost surely, 2^261771505475 is an apocalyptic number.

261771505475 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

261771505475 is a deficient number, since it is larger than the sum of its proper divisors (62825161345).

261771505475 is a wasteful number, since it uses less digits than its factorization.

261771505475 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10470860229 (or 10470860224 counting only the distinct ones).

The product of its (nonzero) digits is 2058000, while the sum is 50.

The spelling of 261771505475 in words is "two hundred sixty-one billion, seven hundred seventy-one million, five hundred five thousand, four hundred seventy-five".