213432011981 has 2 divisors, whose sum is σ = 213432011982. Its totient is φ = 213432011980.

The previous prime is 213432011963. The next prime is 213432012049. The reversal of 213432011981 is 189110234312.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 119618447881 + 93813564100 = 345859^2 + 306290^2 .

It is a cyclic number.

It is not a de Polignac number, because 213432011981 - 2⁶ = 213432011917 is a prime.

It is a super-2 number, since 2×213432011981² (a number of 23 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (213432011581) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 106716005990 + 106716005991.

It is an arithmetic number, because the mean of its divisors is an integer number (106716005991).

Almost surely, 2^213432011981 is an apocalyptic number.

It is an amenable number.

213432011981 is a deficient number, since it is larger than the sum of its proper divisors (1).

213432011981 is an equidigital number, since it uses as much as digits as its factorization.

213432011981 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 10368, while the sum is 35.

The spelling of 213432011981 in words is "two hundred thirteen billion, four hundred thirty-two million, eleven thousand, nine hundred eighty-one".