21541049 has 2 divisors, whose sum is σ = 21541050. Its totient is φ = 21541048.

The previous prime is 21541043. The next prime is 21541061. The reversal of 21541049 is 94014512.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 21529600 + 11449 = 4640^2 + 107^2 .

It is a cyclic number.

It is not a de Polignac number, because 21541049 - 2⁴ = 21541033 is a prime.

It is a Sophie Germain prime.

It is a Chen prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (21541043) 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, 10770524 + 10770525.

It is an arithmetic number, because the mean of its divisors is an integer number (10770525).

Almost surely, 2^21541049 is an apocalyptic number.

It is an amenable number.

21541049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21541049 is an equidigital number, since it uses as much as digits as its factorization.

21541049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 1440, while the sum is 26.

The square root of 21541049 is about 4641.2335644740. The cubic root of 21541049 is about 278.2417414894.

The spelling of 21541049 in words is "twenty-one million, five hundred forty-one thousand, forty-nine".