21395779587822 has 32 divisors (see below), whose sum is σ = 42831373272480. Its totient is φ = 7125291952640.

The previous prime is 21395779587781. The next prime is 21395779587829. The reversal of 21395779587822 is 22878597759312.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21395779587829) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (29) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 80903704 + ... + 81167732.

It is an arithmetic number, because the mean of its divisors is an integer number (1338480414765).

Almost surely, 2^{21395779587822} is an apocalyptic number.

21395779587822 is an abundant number, since it is smaller than the sum of its proper divisors (21435593684658).

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

21395779587822 is a wasteful number, since it uses less digits than its factorization.

21395779587822 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 276548.

The product of its digits is 1066867200, while the sum is 75.

The spelling of 21395779587822 in words is "twenty-one trillion, three hundred ninety-five billion, seven hundred seventy-nine million, five hundred eighty-seven thousand, eight hundred twenty-two".