27878763889 has 16 divisors (see below), whose sum is σ = 28802683728. Its totient is φ = 26971656192.

The previous prime is 27878763881. The next prime is 27878763893. The reversal of 27878763889 is 98836787872.

It can be written as a sum of positive squares in 8 ways, for example, as 977187600 + 26901576289 = 31260^2 + 164017^2 .

It is a cyclic number.

It is not a de Polignac number, because 27878763889 - 2³ = 27878763881 is a prime.

It is a super-2 number, since 2×27878763889² (a number of 22 digits) contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (27878763881) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1414269 + ... + 1433845.

It is an arithmetic number, because the mean of its divisors is an integer number (1800167733).

Almost surely, 2^27878763889 is an apocalyptic number.

It is an amenable number.

27878763889 is a deficient number, since it is larger than the sum of its proper divisors (923919839).

27878763889 is a wasteful number, since it uses less digits than its factorization.

27878763889 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20004.

The product of its digits is 455196672, while the sum is 73.

The spelling of 27878763889 in words is "twenty-seven billion, eight hundred seventy-eight million, seven hundred sixty-three thousand, eight hundred eighty-nine".