20402441 has 2 divisors, whose sum is σ = 20402442. Its totient is φ = 20402440.

The previous prime is 20402419. The next prime is 20402443. The reversal of 20402441 is 14420402.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19360000 + 1042441 = 4400^2 + 1021^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-20402441 is a prime.

Together with 20402443, 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 (20402443) 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, 10201220 + 10201221.

It is an arithmetic number, because the mean of its divisors is an integer number (10201221).

Almost surely, 2^20402441 is an apocalyptic number.

It is an amenable number.

20402441 is a deficient number, since it is larger than the sum of its proper divisors (1).

20402441 is an equidigital number, since it uses as much as digits as its factorization.

20402441 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 256, while the sum is 17.

The square root of 20402441 is about 4516.9061314134. The cubic root of 20402441 is about 273.2503394996.

Adding to 20402441 its reverse (14420402), we get a palindrome (34822843).

The spelling of 20402441 in words is "twenty million, four hundred two thousand, four hundred forty-one".