20197799 has 2 divisors, whose sum is σ = 20197800. Its totient is φ = 20197798.

The previous prime is 20197787. The next prime is 20197811. The reversal of 20197799 is 99779102.

It is a balanced prime because it is at equal distance from previous prime (20197787) and next prime (20197811).

It is a cyclic number.

It is not a de Polignac number, because 20197799 - 2⁴ = 20197783 is a prime.

It is a Sophie Germain prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20197739) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10098899 + 10098900.

It is an arithmetic number, because the mean of its divisors is an integer number (10098900).

Almost surely, 2^20197799 is an apocalyptic number.

20197799 is a deficient number, since it is larger than the sum of its proper divisors (1).

20197799 is an equidigital number, since it uses as much as digits as its factorization.

20197799 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 71442, while the sum is 44.

The square root of 20197799 is about 4494.1961461423. The cubic root of 20197799 is about 272.3336762433. Note that the first 3 decimals are identical.

The spelling of 20197799 in words is "twenty million, one hundred ninety-seven thousand, seven hundred ninety-nine".