20217427 has 2 divisors, whose sum is σ = 20217428. Its totient is φ = 20217426.

The previous prime is 20217409. The next prime is 20217467. The reversal of 20217427 is 72471202.

It is a weak prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20217427 is a prime.

It is not a weakly prime, because it can be changed into another prime (20217467) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10108713 + 10108714.

It is an arithmetic number, because the mean of its divisors is an integer number (10108714).

Almost surely, 2^20217427 is an apocalyptic number.

20217427 is a deficient number, since it is larger than the sum of its proper divisors (1).

20217427 is an equidigital number, since it uses as much as digits as its factorization.

20217427 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1568, while the sum is 25.

The square root of 20217427 is about 4496.3793211872. The cubic root of 20217427 is about 272.4218646445.

Adding to 20217427 its reverse (72471202), we get a palindrome (92688629).

The spelling of 20217427 in words is "twenty million, two hundred seventeen thousand, four hundred twenty-seven".