21256080288 has 48 divisors (see below), whose sum is σ = 59079404160. Its totient is φ = 6668573696.

The previous prime is 21256080281. The next prime is 21256080301. The reversal of 21256080288 is 88208065212.

It is a tau number, because it is divible by the number of its divisors (48).

It is a hoax number, since the sum of its digits (42) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (21256080281) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 6510648 + ... + 6513911.

It is an arithmetic number, because the mean of its divisors is an integer number (1230820920).

Almost surely, 2^21256080288 is an apocalyptic number.

It is an amenable number.

21256080288 is an abundant number, since it is smaller than the sum of its proper divisors (37823323872).

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

21256080288 is a wasteful number, since it uses less digits than its factorization.

21256080288 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 13024589 (or 13024581 counting only the distinct ones).

The product of its (nonzero) digits is 122880, while the sum is 42.

The spelling of 21256080288 in words is "twenty-one billion, two hundred fifty-six million, eighty thousand, two hundred eighty-eight".