20218375091 has 2 divisors, whose sum is σ = 20218375092. Its totient is φ = 20218375090.

The previous prime is 20218374991. The next prime is 20218375189. The reversal of 20218375091 is 19057381202.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20218375091 - 2²⁶ = 20151266227 is a prime.

It is not a weakly prime, because it can be changed into another prime (20218375291) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10109187545 + 10109187546.

It is an arithmetic number, because the mean of its divisors is an integer number (10109187546).

Almost surely, 2^20218375091 is an apocalyptic number.

20218375091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20218375091 is an equidigital number, since it uses as much as digits as its factorization.

20218375091 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 30240, while the sum is 38.

The spelling of 20218375091 in words is "twenty billion, two hundred eighteen million, three hundred seventy-five thousand, ninety-one".