26689906736640 has 6400 divisors, whose sum is σ = 131089785716736. Its totient is φ = 5045118566400.

The previous prime is 26689906736527. The next prime is 26689906736641. The reversal of 26689906736640 is 4663760998662.

26689906736640 is a `hidden beast` number, since 2 + 6 + 6 + 89 + 90 + 67 + 366 + 40 = 666.

It is a super-2 number, since 2×26689906736640² (a number of 28 digits) contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (72).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26689906736641) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 639 ways as a sum of consecutive naturals, for example, 650973335020 + ... + 650973335060.

Almost surely, 2^{26689906736640} is an apocalyptic number.

26689906736640 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 26689906736640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (65544892858368).

26689906736640 is an abundant number, since it is smaller than the sum of its proper divisors (104399878980096).

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

26689906736640 is a wasteful number, since it uses less digits than its factorization.

26689906736640 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 191 (or 166 counting only the distinct ones).

The product of its (nonzero) digits is 846526464, while the sum is 72.

The spelling of 26689906736640 in words is "twenty-six trillion, six hundred eighty-nine billion, nine hundred six million, seven hundred thirty-six thousand, six hundred forty".