10212209981 has 2 divisors, whose sum is σ = 10212209982. Its totient is φ = 10212209980.

The previous prime is 10212209977. The next prime is 10212209983. The reversal of 10212209981 is 18990221201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 9852349081 + 359860900 = 99259^2 + 18970^2 .

It is a cyclic number.

It is not a de Polignac number, because 10212209981 - 2² = 10212209977 is a prime.

It is a super-2 number, since 2×10212209981² (a number of 21 digits) contains 22 as substring.

Together with 10212209983, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (10212209983) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5106104990 + 5106104991.

It is an arithmetic number, because the mean of its divisors is an integer number (5106104991).

Almost surely, 2^10212209981 is an apocalyptic number.

It is an amenable number.

10212209981 is a deficient number, since it is larger than the sum of its proper divisors (1).

10212209981 is an equidigital number, since it uses as much as digits as its factorization.

10212209981 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 5184, while the sum is 35.

The spelling of 10212209981 in words is "ten billion, two hundred twelve million, two hundred nine thousand, nine hundred eighty-one".