21260135244544 has 72 divisors (see below), whose sum is σ = 49044624158880. Its totient is φ = 9009110212608.

The previous prime is 21260135244527. The next prime is 21260135244559. The reversal of 21260135244544 is 44544253106212.

It is a self number, because there is not a number n which added to its sum of digits gives 21260135244544.

It is an unprimeable number.

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, 66491719 + ... + 66810694.

It is an arithmetic number, because the mean of its divisors is an integer number (681175335540).

Almost surely, 2^{21260135244544} is an apocalyptic number.

It is an amenable number.

21260135244544 is an abundant number, since it is smaller than the sum of its proper divisors (27784488914336).

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

21260135244544 is an equidigital number, since it uses as much as digits as its factorization.

21260135244544 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 133302525 (or 133302511 counting only the distinct ones).

The product of its (nonzero) digits is 921600, while the sum is 43.

The spelling of 21260135244544 in words is "twenty-one trillion, two hundred sixty billion, one hundred thirty-five million, two hundred forty-four thousand, five hundred forty-four".