21167147 has 2 divisors, whose sum is σ = 21167148. Its totient is φ = 21167146.

The previous prime is 21167143. The next prime is 21167149. The reversal of 21167147 is 74176112.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21167147 - 2² = 21167143 is a prime.

It is a super-2 number, since 2×21167147² = 896096224239218, which contains 22 as substring.

Together with 21167149, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21167143) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10583573 + 10583574.

It is an arithmetic number, because the mean of its divisors is an integer number (10583574).

Almost surely, 2^21167147 is an apocalyptic number.

21167147 is a deficient number, since it is larger than the sum of its proper divisors (1).

21167147 is an equidigital number, since it uses as much as digits as its factorization.

21167147 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 2352, while the sum is 29.

The square root of 21167147 is about 4600.7767822401. The cubic root of 21167147 is about 276.6224617686.

The spelling of 21167147 in words is "twenty-one million, one hundred sixty-seven thousand, one hundred forty-seven".