20221547 has 2 divisors, whose sum is σ = 20221548. Its totient is φ = 20221546.

The previous prime is 20221541. The next prime is 20221549. The reversal of 20221547 is 74512202.

It is a happy number.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20221547 - 2¹⁸ = 19959403 is a prime.

Together with 20221549, 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 (20221541) 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, 10110773 + 10110774.

It is an arithmetic number, because the mean of its divisors is an integer number (10110774).

Almost surely, 2^20221547 is an apocalyptic number.

20221547 is a deficient number, since it is larger than the sum of its proper divisors (1).

20221547 is an equidigital number, since it uses as much as digits as its factorization.

20221547 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1120, while the sum is 23.

The square root of 20221547 is about 4496.8374442490. The cubic root of 20221547 is about 272.4403685133.

Adding to 20221547 its reverse (74512202), we get a palindrome (94733749).

The spelling of 20221547 in words is "twenty million, two hundred twenty-one thousand, five hundred forty-seven".