26251691504640 has 352 divisors, whose sum is σ = 96714943463424. Its totient is φ = 5953136394240.

The previous prime is 26251691504639. The next prime is 26251691504663. The reversal of 26251691504640 is 4640519615262.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 12693795 + ... + 14616285.

It is an arithmetic number, because the mean of its divisors is an integer number (274758362112).

Almost surely, 2^{26251691504640} is an apocalyptic number.

26251691504640 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 26251691504640, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (48357471731712).

26251691504640 is an abundant number, since it is smaller than the sum of its proper divisors (70463251958784).

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

26251691504640 is a wasteful number, since it uses less digits than its factorization.

26251691504640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1922653 (or 1922635 counting only the distinct ones).

The product of its (nonzero) digits is 3110400, while the sum is 51.

The spelling of 26251691504640 in words is "twenty-six trillion, two hundred fifty-one billion, six hundred ninety-one million, five hundred four thousand, six hundred forty".