21221112001213 has 4 divisors (see below), whose sum is σ = 22143769044768. Its totient is φ = 20298454957660.

The previous prime is 21221112001097. The next prime is 21221112001253. The reversal of 21221112001213 is 31210021112212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21221112001213 - 2²¹ = 21221109904061 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21221112001253) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 461328521743 + ... + 461328521788.

It is an arithmetic number, because the mean of its divisors is an integer number (5535942261192).

Almost surely, 2^{21221112001213} is an apocalyptic number.

21221112001213 is a gapful number since it is divisible by the number (23) formed by its first and last digit.

It is an amenable number.

21221112001213 is a deficient number, since it is larger than the sum of its proper divisors (922657043555).

21221112001213 is an equidigital number, since it uses as much as digits as its factorization.

21221112001213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 922657043554.

The product of its (nonzero) digits is 96, while the sum is 19.

Adding to 21221112001213 its reverse (31210021112212), we get a palindrome (52431133113425).

The spelling of 21221112001213 in words is "twenty-one trillion, two hundred twenty-one billion, one hundred twelve million, one thousand, two hundred thirteen".