21910349 has 4 divisors (see below), whose sum is σ = 22419936. Its totient is φ = 21400764.

The previous prime is 21910321. The next prime is 21910351. The reversal of 21910349 is 94301912.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21910349 - 2²⁰ = 20861773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21910309) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 254729 + ... + 254814.

It is an arithmetic number, because the mean of its divisors is an integer number (5604984).

Almost surely, 2^21910349 is an apocalyptic number.

It is an amenable number.

21910349 is a deficient number, since it is larger than the sum of its proper divisors (509587).

21910349 is an equidigital number, since it uses as much as digits as its factorization.

21910349 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 509586.

The product of its (nonzero) digits is 1944, while the sum is 29.

The square root of 21910349 is about 4680.8491750963. The cubic root of 21910349 is about 279.8228002967.

The spelling of 21910349 in words is "twenty-one million, nine hundred ten thousand, three hundred forty-nine".