20997467 has 2 divisors, whose sum is σ = 20997468. Its totient is φ = 20997466.

The previous prime is 20997461. The next prime is 20997491. The reversal of 20997467 is 76479902.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20997467 - 2⁸ = 20997211 is a prime.

It is not a weakly prime, because it can be changed into another prime (20997461) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10498733 + 10498734.

It is an arithmetic number, because the mean of its divisors is an integer number (10498734).

Almost surely, 2^20997467 is an apocalyptic number.

20997467 is a deficient number, since it is larger than the sum of its proper divisors (1).

20997467 is an equidigital number, since it uses as much as digits as its factorization.

20997467 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 190512, while the sum is 44.

The square root of 20997467 is about 4582.2993136634. The cubic root of 20997467 is about 275.8813245652.

The spelling of 20997467 in words is "twenty million, nine hundred ninety-seven thousand, four hundred sixty-seven".