20387441 has 2 divisors, whose sum is σ = 20387442. Its totient is φ = 20387440.

The previous prime is 20387431. The next prime is 20387443. The reversal of 20387441 is 14478302.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20295025 + 92416 = 4505^2 + 304^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20387441 is a prime.

Together with 20387443, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (20387443) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10193720 + 10193721.

It is an arithmetic number, because the mean of its divisors is an integer number (10193721).

Almost surely, 2^20387441 is an apocalyptic number.

It is an amenable number.

20387441 is a deficient number, since it is larger than the sum of its proper divisors (1).

20387441 is an equidigital number, since it uses as much as digits as its factorization.

20387441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 5376, while the sum is 29.

The square root of 20387441 is about 4515.2453975393. The cubic root of 20387441 is about 273.1833579722.

The spelling of 20387441 in words is "twenty million, three hundred eighty-seven thousand, four hundred forty-one".