20514581 has 2 divisors, whose sum is σ = 20514582. Its totient is φ = 20514580.

The previous prime is 20514577. The next prime is 20514583. The reversal of 20514581 is 18541502.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19722481 + 792100 = 4441^2 + 890^2 .

It is a cyclic number.

It is not a de Polignac number, because 20514581 - 2² = 20514577 is a prime.

It is a super-2 number, since 2×20514581² = 841696067211122, which contains 22 as substring.

Together with 20514583, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20514581.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20514583) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10257290 + 10257291.

It is an arithmetic number, because the mean of its divisors is an integer number (10257291).

Almost surely, 2^20514581 is an apocalyptic number.

It is an amenable number.

20514581 is a deficient number, since it is larger than the sum of its proper divisors (1).

20514581 is an equidigital number, since it uses as much as digits as its factorization.

20514581 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1600, while the sum is 26.

The square root of 20514581 is about 4529.3024849308. The cubic root of 20514581 is about 273.7500562262.

The spelling of 20514581 in words is "twenty million, five hundred fourteen thousand, five hundred eighty-one".