26401808640 has 144 divisors (see below), whose sum is σ = 85337719488. Its totient is φ = 6955573248.

The previous prime is 26401808621. The next prime is 26401808647. The reversal of 26401808640 is 4680810462.

It is not an unprimeable number, because it can be changed into a prime (26401808647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 277302 + ... + 360138.

It is an arithmetic number, because the mean of its divisors is an integer number (592623052).

Almost surely, 2^26401808640 is an apocalyptic number.

26401808640 is a gapful number since it is divisible by the number (20) 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 26401808640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (42668859744).

26401808640 is an abundant number, since it is smaller than the sum of its proper divisors (58935910848).

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

26401808640 is an equidigital number, since it uses as much as digits as its factorization.

26401808640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 82944 (or 82930 counting only the distinct ones).

The product of its (nonzero) digits is 73728, while the sum is 39.

The spelling of 26401808640 in words is "twenty-six billion, four hundred one million, eight hundred eight thousand, six hundred forty".