21106049 has 2 divisors, whose sum is σ = 21106050. Its totient is φ = 21106048.

The previous prime is 21106037. The next prime is 21106051. The reversal of 21106049 is 94060112.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10660225 + 10445824 = 3265^2 + 3232^2 .

It is a cyclic number.

It is not a de Polignac number, because 21106049 - 2²⁴ = 4328833 is a prime.

Together with 21106051, 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 (21106079) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10553024 + 10553025.

It is an arithmetic number, because the mean of its divisors is an integer number (10553025).

Almost surely, 2^21106049 is an apocalyptic number.

It is an amenable number.

21106049 is a deficient number, since it is larger than the sum of its proper divisors (1).

21106049 is an equidigital number, since it uses as much as digits as its factorization.

21106049 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 432, while the sum is 23.

The square root of 21106049 is about 4594.1320181292. The cubic root of 21106049 is about 276.3560525907.

The spelling of 21106049 in words is "twenty-one million, one hundred six thousand, forty-nine".