21410749 has 2 divisors, whose sum is σ = 21410750. Its totient is φ = 21410748.

The previous prime is 21410747. The next prime is 21410773. The reversal of 21410749 is 94701412.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 20994724 + 416025 = 4582^2 + 645^2 .

It is a cyclic number.

It is not a de Polignac number, because 21410749 - 2¹ = 21410747 is a prime.

Together with 21410747, it forms a pair of twin primes.

It is a Chen prime.

It is an alternating number because its digits alternate between even and odd.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21410747) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10705374 + 10705375.

It is an arithmetic number, because the mean of its divisors is an integer number (10705375).

Almost surely, 2^21410749 is an apocalyptic number.

It is an amenable number.

21410749 is a deficient number, since it is larger than the sum of its proper divisors (1).

21410749 is an equidigital number, since it uses as much as digits as its factorization.

21410749 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2016, while the sum is 28.

The square root of 21410749 is about 4627.1750561223. The cubic root of 21410749 is about 277.6795861595.

The spelling of 21410749 in words is "twenty-one million, four hundred ten thousand, seven hundred forty-nine".