20897047 has 2 divisors, whose sum is σ = 20897048. Its totient is φ = 20897046.

The previous prime is 20897039. The next prime is 20897057. The reversal of 20897047 is 74079802.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20897047 - 2³ = 20897039 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20896997 and 20897015.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20897027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10448523 + 10448524.

It is an arithmetic number, because the mean of its divisors is an integer number (10448524).

Almost surely, 2^20897047 is an apocalyptic number.

20897047 is a deficient number, since it is larger than the sum of its proper divisors (1).

20897047 is an equidigital number, since it uses as much as digits as its factorization.

20897047 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 28224, while the sum is 37.

The square root of 20897047 is about 4571.3288002505. The cubic root of 20897047 is about 275.4408224647.

The spelling of 20897047 in words is "twenty million, eight hundred ninety-seven thousand, forty-seven".