21055023213 has 8 divisors (see below), whose sum is σ = 32083844928. Its totient is φ = 12031441824.

The previous prime is 21055023173. The next prime is 21055023221. The reversal of 21055023213 is 31232055012.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is not a de Polignac number, because 21055023213 - 2¹⁴ = 21055006829 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21055023113) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 501310056 + ... + 501310097.

It is an arithmetic number, because the mean of its divisors is an integer number (4010480616).

Almost surely, 2^21055023213 is an apocalyptic number.

It is an amenable number.

21055023213 is a deficient number, since it is larger than the sum of its proper divisors (11028821715).

21055023213 is a wasteful number, since it uses less digits than its factorization.

21055023213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1002620163.

The product of its (nonzero) digits is 1800, while the sum is 24.

Adding to 21055023213 its reverse (31232055012), we get a palindrome (52287078225).

The spelling of 21055023213 in words is "twenty-one billion, fifty-five million, twenty-three thousand, two hundred thirteen".