21021102213 has 16 divisors (see below), whose sum is σ = 28764218496. Its totient is φ = 13650488640.

The previous prime is 21021102209. The next prime is 21021102283. The reversal of 21021102213 is 31220112012.

It is not a de Polignac number, because 21021102213 - 2² = 21021102209 is a prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 21021102192 and 21021102201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21021102283) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 538770 + ... + 576467.

It is an arithmetic number, because the mean of its divisors is an integer number (1797763656).

Almost surely, 2^21021102213 is an apocalyptic number.

It is an amenable number.

21021102213 is a deficient number, since it is larger than the sum of its proper divisors (7743116283).

21021102213 is a wasteful number, since it uses less digits than its factorization.

21021102213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1115404.

The product of its (nonzero) digits is 48, while the sum is 15.

Adding to 21021102213 its reverse (31220112012), we get a palindrome (52241214225).

The spelling of 21021102213 in words is "twenty-one billion, twenty-one million, one hundred two thousand, two hundred thirteen".