21012012067 has 2 divisors, whose sum is σ = 21012012068. Its totient is φ = 21012012066.

The previous prime is 21012011989. The next prime is 21012012079. The reversal of 21012012067 is 76021021012.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21012012067 is a prime.

It is a super-2 number, since 2×21012012067² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (21012013067) 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, 10506006033 + 10506006034.

It is an arithmetic number, because the mean of its divisors is an integer number (10506006034).

Almost surely, 2^21012012067 is an apocalyptic number.

21012012067 is a deficient number, since it is larger than the sum of its proper divisors (1).

21012012067 is an equidigital number, since it uses as much as digits as its factorization.

21012012067 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 336, while the sum is 22.

Adding to 21012012067 its reverse (76021021012), we get a palindrome (97033033079).

The spelling of 21012012067 in words is "twenty-one billion, twelve million, twelve thousand, sixty-seven".