26617720064 has 144 divisors (see below), whose sum is σ = 59539880400. Its totient is φ = 11791761408.

The previous prime is 26617720057. The next prime is 26617720067. The reversal of 26617720064 is 46002771662.

It can be written as a sum of positive squares in 8 ways, for example, as 7990929664 + 18626790400 = 89392^2 + 136480^2 .

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (26617720067) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18626102 + ... + 18627530.

Almost surely, 2^26617720064 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 26617720064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29769940200).

26617720064 is an abundant number, since it is smaller than the sum of its proper divisors (32922160336).

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

26617720064 is a wasteful number, since it uses less digits than its factorization.

26617720064 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1680 (or 1666 counting only the distinct ones).

The product of its (nonzero) digits is 169344, while the sum is 41.

The spelling of 26617720064 in words is "twenty-six billion, six hundred seventeen million, seven hundred twenty thousand, sixty-four".