27778361117 has 4 divisors (see below), whose sum is σ = 29915158140. Its totient is φ = 25641564096.

The previous prime is 27778361089. The next prime is 27778361119. The reversal of 27778361117 is 71116387772.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 2028061156 + 25750299961 = 45034^2 + 160469^2 .

It is a cyclic number.

It is not a de Polignac number, because 27778361117 - 2¹² = 27778357021 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (27778361119) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1068398492 + ... + 1068398517.

It is an arithmetic number, because the mean of its divisors is an integer number (7478789535).

Almost surely, 2^27778361117 is an apocalyptic number.

It is an amenable number.

27778361117 is a deficient number, since it is larger than the sum of its proper divisors (2136797023).

27778361117 is a wasteful number, since it uses less digits than its factorization.

27778361117 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2136797022.

The product of its digits is 691488, while the sum is 50.

The spelling of 27778361117 in words is "twenty-seven billion, seven hundred seventy-eight million, three hundred sixty-one thousand, one hundred seventeen".