21542112213 has 16 divisors (see below), whose sum is σ = 29769759360. Its totient is φ = 13845059136.

The previous prime is 21542112197. The next prime is 21542112223. The reversal of 21542112213 is 31221124512.

It is a happy number.

It is not a de Polignac number, because 21542112213 - 2⁴ = 21542112197 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21542112223) 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 15 ways as a sum of consecutive naturals, for example, 878145 + ... + 902342.

It is an arithmetic number, because the mean of its divisors is an integer number (1860609960).

Almost surely, 2^21542112213 is an apocalyptic number.

It is an amenable number.

21542112213 is a deficient number, since it is larger than the sum of its proper divisors (8227647147).

21542112213 is a wasteful number, since it uses less digits than its factorization.

21542112213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1780636.

The product of its digits is 960, while the sum is 24.

Adding to 21542112213 its reverse (31221124512), we get a palindrome (52763236725).

The spelling of 21542112213 in words is "twenty-one billion, five hundred forty-two million, one hundred twelve thousand, two hundred thirteen".