20697052091 has 2 divisors, whose sum is σ = 20697052092. Its totient is φ = 20697052090.

The previous prime is 20697052073. The next prime is 20697052093. The reversal of 20697052091 is 19025079602.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20697052091 is a prime.

Together with 20697052093, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20697052093) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10348526045 + 10348526046.

It is an arithmetic number, because the mean of its divisors is an integer number (10348526046).

Almost surely, 2^20697052091 is an apocalyptic number.

20697052091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20697052091 is an equidigital number, since it uses as much as digits as its factorization.

20697052091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 68040, while the sum is 41.

The spelling of 20697052091 in words is "twenty billion, six hundred ninety-seven million, fifty-two thousand, ninety-one".