21654421144356 has 192 divisors, whose sum is σ = 68699166842880. Its totient is φ = 5126149117440.

The previous prime is 21654421144297. The next prime is 21654421144381. The reversal of 21654421144356 is 65344112445612.

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 63 ways as a sum of consecutive naturals, for example, 10460751 + ... + 12358646.

It is an arithmetic number, because the mean of its divisors is an integer number (357808160640).

Almost surely, 2^{21654421144356} is an apocalyptic number.

21654421144356 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

21654421144356 is an abundant number, since it is smaller than the sum of its proper divisors (47044745698524).

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

21654421144356 is a wasteful number, since it uses less digits than its factorization.

21654421144356 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22819514 (or 22819512 counting only the distinct ones).

The product of its digits is 2764800, while the sum is 48.

Adding to 21654421144356 its reverse (65344112445612), we get a palindrome (86998533589968).

The spelling of 21654421144356 in words is "twenty-one trillion, six hundred fifty-four billion, four hundred twenty-one million, one hundred forty-four thousand, three hundred fifty-six".