20045791 has 2 divisors, whose sum is σ = 20045792. Its totient is φ = 20045790.

The previous prime is 20045789. The next prime is 20045827. The reversal of 20045791 is 19754002.

It is a happy number.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 20045791 - 2¹ = 20045789 is a prime.

Together with 20045789, it forms a pair of twin primes.

It is a Chen prime.

It is equal to p_1273357 and since 20045791 and 1273357 have the same sum of digits, it is a Honaker prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20045591) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10022895 + 10022896.

It is an arithmetic number, because the mean of its divisors is an integer number (10022896).

Almost surely, 2^20045791 is an apocalyptic number.

20045791 is a deficient number, since it is larger than the sum of its proper divisors (1).

20045791 is an equidigital number, since it uses as much as digits as its factorization.

20045791 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2520, while the sum is 28.

The square root of 20045791 is about 4477.2526173983. The cubic root of 20045791 is about 271.6487635878.

Adding to 20045791 its reverse (19754002), we get a palindrome (39799793).

The spelling of 20045791 in words is "twenty million, forty-five thousand, seven hundred ninety-one".