2117778547 has 8 divisors (see below), whose sum is σ = 2188318592. Its totient is φ = 2047377600.

The previous prime is 2117778527. The next prime is 2117778601. The reversal of 2117778547 is 7458777112.

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

It is a cyclic number.

It is not a de Polignac number, because 2117778547 - 2²⁷ = 1983560819 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2117778547.

It is not an unprimeable number, because it can be changed into a prime (2117778527) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3354 + ... + 65167.

It is an arithmetic number, because the mean of its divisors is an integer number (273539824).

Almost surely, 2^2117778547 is an apocalyptic number.

2117778547 is a deficient number, since it is larger than the sum of its proper divisors (70540045).

2117778547 is an equidigital number, since it uses as much as digits as its factorization.

2117778547 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 69549.

The product of its digits is 768320, while the sum is 49.

The square root of 2117778547 is about 46019.3279720597. The cubic root of 2117778547 is about 1284.1827982467.

The spelling of 2117778547 in words is "two billion, one hundred seventeen million, seven hundred seventy-eight thousand, five hundred forty-seven".