20445904091 has 2 divisors, whose sum is σ = 20445904092. Its totient is φ = 20445904090.

The previous prime is 20445904043. The next prime is 20445904121. The reversal of 20445904091 is 19040954402.

It is a strong prime.

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20445904091 is a prime.

It is not a weakly prime, because it can be changed into another prime (20445904691) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10222952045 + 10222952046.

It is an arithmetic number, because the mean of its divisors is an integer number (10222952046).

Almost surely, 2^20445904091 is an apocalyptic number.

20445904091 is a deficient number, since it is larger than the sum of its proper divisors (1).

20445904091 is an equidigital number, since it uses as much as digits as its factorization.

20445904091 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 51840, while the sum is 38.

The spelling of 20445904091 in words is "twenty billion, four hundred forty-five million, nine hundred four thousand, ninety-one".