26991974880 has 144 divisors (see below), whose sum is σ = 99195576480. Its totient is φ = 6644173824.

The previous prime is 26991974869. The next prime is 26991974881. The reversal of 26991974880 is 8847919962.

26991974880 is a `hidden beast` number, since 2 + 69 + 9 + 1 + 97 + 488 + 0 = 666.

It is a tau number, because it is divible by the number of its divisors (144).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26991974881) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 702220 + ... + 739659.

It is an arithmetic number, because the mean of its divisors is an integer number (688858170).

Almost surely, 2^26991974880 is an apocalyptic number.

26991974880 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

26991974880 is an abundant number, since it is smaller than the sum of its proper divisors (72203601600).

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

26991974880 is a wasteful number, since it uses less digits than its factorization.

26991974880 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1441913 (or 1441902 counting only the distinct ones).

The product of its (nonzero) digits is 15676416, while the sum is 63.

The spelling of 26991974880 in words is "twenty-six billion, nine hundred ninety-one million, nine hundred seventy-four thousand, eight hundred eighty".