21213034389121 has 9 divisors (see below), whose sum is σ = 21236129751081. Its totient is φ = 21189964132272.

The previous prime is 21213034389119. The next prime is 21213034389139. The reversal of 21213034389121 is 12198343031212.

The square root of 21213034389121 is 4605761.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 19136783942721 + 2076250446400 = 4374561^2 + 1440920^2 .

It is not a de Polignac number, because 21213034389121 - 2¹ = 21213034389119 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21213034389181) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 5586786195 + ... + 5586789991.

Almost surely, 2^{21213034389121} is an apocalyptic number.

21213034389121 is the 4605761-st square number.

21213034389121 is the 2302881-st centered octagonal number.

It is an amenable number.

21213034389121 is a deficient number, since it is larger than the sum of its proper divisors (23095361960).

21213034389121 is an frugal number, since it uses more digits than its factorization.

21213034389121 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10020 (or 5010 counting only the distinct ones).

The product of its (nonzero) digits is 62208, while the sum is 40.

The spelling of 21213034389121 in words is "twenty-one trillion, two hundred thirteen billion, thirty-four million, three hundred eighty-nine thousand, one hundred twenty-one".