21189347 has 8 divisors (see below), whose sum is σ = 21658320. Its totient is φ = 20723040.

The previous prime is 21189341. The next prime is 21189397. The reversal of 21189347 is 74398112.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21189347 - 2⁴ = 21189331 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21189341) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 28304 + ... + 29042.

It is an arithmetic number, because the mean of its divisors is an integer number (2707290).

Almost surely, 2^21189347 is an apocalyptic number.

21189347 is a deficient number, since it is larger than the sum of its proper divisors (468973).

21189347 is an equidigital number, since it uses as much as digits as its factorization.

21189347 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1333.

The product of its digits is 12096, while the sum is 35.

The square root of 21189347 is about 4603.1887860482. The cubic root of 21189347 is about 276.7191347403.

The spelling of 21189347 in words is "twenty-one million, one hundred eighty-nine thousand, three hundred forty-seven".