20604247 has 2 divisors, whose sum is σ = 20604248. Its totient is φ = 20604246.

The previous prime is 20604211. The next prime is 20604277. The reversal of 20604247 is 74240602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20604247 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20604277) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10302123 + 10302124.

It is an arithmetic number, because the mean of its divisors is an integer number (10302124).

Almost surely, 2^20604247 is an apocalyptic number.

20604247 is a deficient number, since it is larger than the sum of its proper divisors (1).

20604247 is an equidigital number, since it uses as much as digits as its factorization.

20604247 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2688, while the sum is 25.

The square root of 20604247 is about 4539.1901260027. The cubic root of 20604247 is about 274.1483159939.

Adding to 20604247 its reverse (74240602), we get a palindrome (94844849).

The spelling of 20604247 in words is "twenty million, six hundred four thousand, two hundred forty-seven".