21221100067 has 2 divisors, whose sum is σ = 21221100068. Its totient is φ = 21221100066.

The previous prime is 21221100031. The next prime is 21221100091. The reversal of 21221100067 is 76000112212.

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-21221100067 is a prime.

It is not a weakly prime, because it can be changed into another prime (21221100007) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610550033 + 10610550034.

It is an arithmetic number, because the mean of its divisors is an integer number (10610550034).

Almost surely, 2^21221100067 is an apocalyptic number.

21221100067 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221100067 is an equidigital number, since it uses as much as digits as its factorization.

21221100067 is an evil number, because the sum of its binary digits is even.

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

Adding to 21221100067 its reverse (76000112212), we get a palindrome (97221212279).

The spelling of 21221100067 in words is "twenty-one billion, two hundred twenty-one million, one hundred thousand, sixty-seven".