21549049 has 2 divisors, whose sum is σ = 21549050. Its totient is φ = 21549048.

The previous prime is 21549019. The next prime is 21549071. The reversal of 21549049 is 94094512.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 20539024 + 1010025 = 4532^2 + 1005^2 .

It is a cyclic number.

It is not a de Polignac number, because 21549049 - 2¹⁵ = 21516281 is a prime.

It is not a weakly prime, because it can be changed into another prime (21549019) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10774524 + 10774525.

It is an arithmetic number, because the mean of its divisors is an integer number (10774525).

Almost surely, 2^21549049 is an apocalyptic number.

It is an amenable number.

21549049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21549049 is an equidigital number, since it uses as much as digits as its factorization.

21549049 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12960, while the sum is 34.

The square root of 21549049 is about 4642.0953243121. The cubic root of 21549049 is about 278.2761820657.

The spelling of 21549049 in words is "twenty-one million, five hundred forty-nine thousand, forty-nine".