20697071 has 2 divisors, whose sum is σ = 20697072. Its totient is φ = 20697070.

The previous prime is 20697049. The next prime is 20697077. The reversal of 20697071 is 17079602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20697071 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20697077) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10348535 + 10348536.

It is an arithmetic number, because the mean of its divisors is an integer number (10348536).

Almost surely, 2^20697071 is an apocalyptic number.

20697071 is a deficient number, since it is larger than the sum of its proper divisors (1).

20697071 is an equidigital number, since it uses as much as digits as its factorization.

20697071 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5292, while the sum is 32.

The square root of 20697071 is about 4549.4033674758. The cubic root of 20697071 is about 274.5593869760.

The spelling of 20697071 in words is "twenty million, six hundred ninety-seven thousand, seventy-one".