21212011099973 has 2 divisors, whose sum is σ = 21212011099974. Its totient is φ = 21212011099972.

The previous prime is 21212011099927. The next prime is 21212011100057. The reversal of 21212011099973 is 37999011021212.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21080421360964 + 131589739009 = 4591342^2 + 362753^2 .

It is a cyclic number.

It is not a de Polignac number, because 21212011099973 - 2¹⁶ = 21212011034437 is a prime.

It is a super-2 number, since 2×21212011099973² (a number of 27 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21232011099973) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10606005549986 + 10606005549987.

It is an arithmetic number, because the mean of its divisors is an integer number (10606005549987).

Almost surely, 2^{21212011099973} is an apocalyptic number.

It is an amenable number.

21212011099973 is a deficient number, since it is larger than the sum of its proper divisors (1).

21212011099973 is an equidigital number, since it uses as much as digits as its factorization.

21212011099973 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 122472, while the sum is 47.

The spelling of 21212011099973 in words is "twenty-one trillion, two hundred twelve billion, eleven million, ninety-nine thousand, nine hundred seventy-three".