20797897 has 2 divisors, whose sum is σ = 20797898. Its totient is φ = 20797896.

The previous prime is 20797883. The next prime is 20797921. The reversal of 20797897 is 79879702.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 12595401 + 8202496 = 3549^2 + 2864^2 .

It is a cyclic number.

It is not a de Polignac number, because 20797897 - 2⁷ = 20797769 is a prime.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20797897.

It is not a weakly prime, because it can be changed into another prime (20797877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10398948 + 10398949.

It is an arithmetic number, because the mean of its divisors is an integer number (10398949).

Almost surely, 2^20797897 is an apocalyptic number.

It is an amenable number.

20797897 is a deficient number, since it is larger than the sum of its proper divisors (1).

20797897 is an equidigital number, since it uses as much as digits as its factorization.

20797897 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 444528, while the sum is 49.

The square root of 20797897 is about 4560.4711379418. The cubic root of 20797897 is about 275.0045046094.

The spelling of 20797897 in words is "twenty million, seven hundred ninety-seven thousand, eight hundred ninety-seven".