21012120221213 has 16 divisors (see below), whose sum is σ = 24101470978560. Its totient is φ = 18140892100800.

The previous prime is 21012120221171. The next prime is 21012120221293. The reversal of 21012120221213 is 31212202121012.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21012120221213 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 (21012120221293) 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, 539888045 + ... + 539926962.

It is an arithmetic number, because the mean of its divisors is an integer number (1506341936160).

Almost surely, 2^{21012120221213} is an apocalyptic number.

It is an amenable number.

21012120221213 is a deficient number, since it is larger than the sum of its proper divisors (3089350757347).

21012120221213 is a wasteful number, since it uses less digits than its factorization.

21012120221213 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1079815108.

The product of its (nonzero) digits is 192, while the sum is 20.

Adding to 21012120221213 its reverse (31212202121012), we get a palindrome (52224322342225).

The spelling of 21012120221213 in words is "twenty-one trillion, twelve billion, one hundred twenty million, two hundred twenty-one thousand, two hundred thirteen".