8261778165 has 8 divisors (see below), whose sum is σ = 13218845088. Its totient is φ = 4406281680.

The previous prime is 8261778143. The next prime is 8261778191. The reversal of 8261778165 is 5618771628.

It is a happy number.

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

It is not a de Polignac number, because 8261778165 - 2²⁴ = 8245000949 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, 275392591 + ... + 275392620.

It is an arithmetic number, because the mean of its divisors is an integer number (1652355636).

Almost surely, 2^8261778165 is an apocalyptic number.

It is an amenable number.

8261778165 is a deficient number, since it is larger than the sum of its proper divisors (4957066923).

8261778165 is a wasteful number, since it uses less digits than its factorization.

8261778165 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 550785219.

The product of its digits is 1128960, while the sum is 51.

The square root of 8261778165 is about 90894.3241627331. The cubic root of 8261778165 is about 2021.5811367421.

The spelling of 8261778165 in words is "eight billion, two hundred sixty-one million, seven hundred seventy-eight thousand, one hundred sixty-five".