26638592640 has 1024 divisors, whose sum is σ = 104907571200. Its totient is φ = 5677056000.

The previous prime is 26638592623. The next prime is 26638592641. The reversal of 26638592640 is 4629583662.

It is a super-2 number, since 2×26638592640² (a number of 22 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (51) coincides with the sum of the digits of its prime factors.

It is not an unprimeable number, because it can be changed into a prime (26638592641) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 436698210 + ... + 436698270.

It is an arithmetic number, because the mean of its divisors is an integer number (102448800).

Almost surely, 2^26638592640 is an apocalyptic number.

26638592640 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 26638592640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (52453785600).

26638592640 is an abundant number, since it is smaller than the sum of its proper divisors (78268978560).

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

26638592640 is a wasteful number, since it uses less digits than its factorization.

26638592640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 177 (or 165 counting only the distinct ones).

The product of its (nonzero) digits is 3732480, while the sum is 51.

The spelling of 26638592640 in words is "twenty-six billion, six hundred thirty-eight million, five hundred ninety-two thousand, six hundred forty".