20868847 has 2 divisors, whose sum is σ = 20868848. Its totient is φ = 20868846.

The previous prime is 20868839. The next prime is 20868853. The reversal of 20868847 is 74886802.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20868847 - 2³ = 20868839 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20868857) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10434423 + 10434424.

It is an arithmetic number, because the mean of its divisors is an integer number (10434424).

Almost surely, 2^20868847 is an apocalyptic number.

20868847 is a deficient number, since it is larger than the sum of its proper divisors (1).

20868847 is an equidigital number, since it uses as much as digits as its factorization.

20868847 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 172032, while the sum is 43.

The square root of 20868847 is about 4568.2433166372. The cubic root of 20868847 is about 275.3168667084.

The spelling of 20868847 in words is "twenty million, eight hundred sixty-eight thousand, eight hundred forty-seven".