26403861991680 has 432 divisors, whose sum is σ = 91641130963200. Its totient is φ = 7018979622912.

The previous prime is 26403861991597. The next prime is 26403861991681. The reversal of 26403861991680 is 8619916830462.

26403861991680 is a `hidden beast` number, since 2 + 6 + 4 + 0 + 3 + 8 + 619 + 9 + 1 + 6 + 8 + 0 = 666.

It is not an unprimeable number, because it can be changed into a prime (26403861991681) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 7655510596 + ... + 7655514044.

It is an arithmetic number, because the mean of its divisors is an integer number (212132247600).

Almost surely, 2^{26403861991680} is an apocalyptic number.

26403861991680 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 26403861991680, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (45820565481600).

26403861991680 is an abundant number, since it is smaller than the sum of its proper divisors (65237268971520).

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

26403861991680 is a wasteful number, since it uses less digits than its factorization.

26403861991680 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5366 (or 5349 counting only the distinct ones).

The product of its (nonzero) digits is 26873856, while the sum is 63.

The spelling of 26403861991680 in words is "twenty-six trillion, four hundred three billion, eight hundred sixty-one million, nine hundred ninety-one thousand, six hundred eighty".