21221001167 has 2 divisors, whose sum is σ = 21221001168. Its totient is φ = 21221001166.

The previous prime is 21221001103. The next prime is 21221001199. The reversal of 21221001167 is 76110012212.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21221001167 - 2⁶ = 21221001103 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21221007167) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10610500583 + 10610500584.

It is an arithmetic number, because the mean of its divisors is an integer number (10610500584).

Almost surely, 2^21221001167 is an apocalyptic number.

21221001167 is a deficient number, since it is larger than the sum of its proper divisors (1).

21221001167 is an equidigital number, since it uses as much as digits as its factorization.

21221001167 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 23.

Adding to 21221001167 its reverse (76110012212), we get a palindrome (97331013379).

The spelling of 21221001167 in words is "twenty-one billion, two hundred twenty-one million, one thousand, one hundred sixty-seven".