20027591 has 2 divisors, whose sum is σ = 20027592. Its totient is φ = 20027590.

The previous prime is 20027569. The next prime is 20027597. The reversal of 20027591 is 19572002.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 20027591 - 2²² = 15833287 is a prime.

It is a super-2 number, since 2×20027591² = 802208802526562, which contains 22 as substring.

It is equal to p_1272257 and since 20027591 and 1272257 have the same sum of digits, it is a Honaker prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20027591.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20027597) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10013795 + 10013796.

It is an arithmetic number, because the mean of its divisors is an integer number (10013796).

Almost surely, 2^20027591 is an apocalyptic number.

20027591 is a deficient number, since it is larger than the sum of its proper divisors (1).

20027591 is an equidigital number, since it uses as much as digits as its factorization.

20027591 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 1260, while the sum is 26.

The square root of 20027591 is about 4475.2196594134. The cubic root of 20027591 is about 271.5665267979.

Adding to 20027591 its reverse (19572002), we get a palindrome (39599593).

The spelling of 20027591 in words is "twenty million, twenty-seven thousand, five hundred ninety-one".