27956388864 has 132 divisors (see below), whose sum is σ = 77899092656. Its totient is φ = 8913113088.

The previous prime is 27956388851. The next prime is 27956388869. The reversal of 27956388864 is 46888365972.

It is a super-4 number, since 4×27956388864⁴ (a number of 43 digits) contains 4444 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 27956388795 and 27956388804.

It is not an unprimeable number, because it can be changed into a prime (27956388869) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1616487 + ... + 1633689.

Almost surely, 2^27956388864 is an apocalyptic number.

27956388864 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 27956388864, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (38949546328).

27956388864 is an abundant number, since it is smaller than the sum of its proper divisors (49942703792).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

27956388864 is a wasteful number, since it uses less digits than its factorization.

27956388864 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17272 (or 17231 counting only the distinct ones).

The product of its digits is 139345920, while the sum is 66.

The spelling of 27956388864 in words is "twenty-seven billion, nine hundred fifty-six million, three hundred eighty-eight thousand, eight hundred sixty-four".