21041357 has 2 divisors, whose sum is σ = 21041358. Its totient is φ = 21041356.

The previous prime is 21041353. The next prime is 21041369. The reversal of 21041357 is 75314012.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 15792676 + 5248681 = 3974^2 + 2291^2 .

It is a cyclic number.

It is not a de Polignac number, because 21041357 - 2² = 21041353 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21041353) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520678 + 10520679.

It is an arithmetic number, because the mean of its divisors is an integer number (10520679).

Almost surely, 2^21041357 is an apocalyptic number.

It is an amenable number.

21041357 is a deficient number, since it is larger than the sum of its proper divisors (1).

21041357 is an equidigital number, since it uses as much as digits as its factorization.

21041357 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 840, while the sum is 23.

The square root of 21041357 is about 4587.0858941162. The cubic root of 21041357 is about 276.0734112990.

Adding to 21041357 its reverse (75314012), we get a palindrome (96355369).

The spelling of 21041357 in words is "twenty-one million, forty-one thousand, three hundred fifty-seven".