21013050455 has 4 divisors (see below), whose sum is σ = 25215660552. Its totient is φ = 16810440360.

The previous prime is 21013050449. The next prime is 21013050467. The reversal of 21013050455 is 55405031012.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 21013050455 - 2⁴ = 21013050439 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

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 3 ways as a sum of consecutive naturals, for example, 2101305041 + ... + 2101305050.

It is an arithmetic number, because the mean of its divisors is an integer number (6303915138).

Almost surely, 2^21013050455 is an apocalyptic number.

21013050455 is a deficient number, since it is larger than the sum of its proper divisors (4202610097).

21013050455 is an equidigital number, since it uses as much as digits as its factorization.

21013050455 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4202610096.

The product of its (nonzero) digits is 3000, while the sum is 26.

Adding to 21013050455 its reverse (55405031012), we get a palindrome (76418081467).

The spelling of 21013050455 in words is "twenty-one billion, thirteen million, fifty thousand, four hundred fifty-five".