21498136105 has 4 divisors (see below), whose sum is σ = 25797763332. Its totient is φ = 17198508880.

The previous prime is 21498136081. The next prime is 21498136109. The reversal of 21498136105 is 50163189412.

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

It can be written as a sum of positive squares in 2 ways, for example, as 2718996736 + 18779139369 = 52144^2 + 137037^2 .

It is not a de Polignac number, because 21498136105 - 2¹³ = 21498127913 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21498136109) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2149813606 + ... + 2149813615.

It is an arithmetic number, because the mean of its divisors is an integer number (6449440833).

Almost surely, 2^21498136105 is an apocalyptic number.

It is an amenable number.

21498136105 is a deficient number, since it is larger than the sum of its proper divisors (4299627227).

21498136105 is an equidigital number, since it uses as much as digits as its factorization.

21498136105 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 4299627226.

The product of its (nonzero) digits is 51840, while the sum is 40.

The spelling of 21498136105 in words is "twenty-one billion, four hundred ninety-eight million, one hundred thirty-six thousand, one hundred five".