21213444524506 has 32 divisors (see below), whose sum is σ = 34573453261200. Its totient is φ = 9703523257344.

The previous prime is 21213444524497. The next prime is 21213444524509. The reversal of 21213444524506 is 60542544431212.

It can be written as a sum of positive squares in 8 ways, for example, as 498739626225 + 20714704898281 = 706215^2 + 4551341^2 .

It is not an unprimeable number, because it can be changed into a prime (21213444524509) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 44860156 + ... + 45330568.

Almost surely, 2^{21213444524506} is an apocalyptic number.

21213444524506 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

21213444524506 is a deficient number, since it is larger than the sum of its proper divisors (13360008736694).

21213444524506 is a wasteful number, since it uses less digits than its factorization.

21213444524506 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 485890.

The product of its (nonzero) digits is 921600, while the sum is 43.

Adding to 21213444524506 its reverse (60542544431212), we get a palindrome (81755988955718).

The spelling of 21213444524506 in words is "twenty-one trillion, two hundred thirteen billion, four hundred forty-four million, five hundred twenty-four thousand, five hundred six".