21212113049 has 2 divisors, whose sum is σ = 21212113050. Its totient is φ = 21212113048.

The previous prime is 21212113007. The next prime is 21212113063. The reversal of 21212113049 is 94031121212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 15700090000 + 5512023049 = 125300^2 + 74243^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212113049 - 2¹⁶ = 21212047513 is a prime.

It is not a weakly prime, because it can be changed into another prime (21212113079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606056524 + 10606056525.

It is an arithmetic number, because the mean of its divisors is an integer number (10606056525).

Almost surely, 2^21212113049 is an apocalyptic number.

It is an amenable number.

21212113049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212113049 is an equidigital number, since it uses as much as digits as its factorization.

21212113049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 864, while the sum is 26.

The spelling of 21212113049 in words is "twenty-one billion, two hundred twelve million, one hundred thirteen thousand, forty-nine".