21297849 has 8 divisors (see below), whose sum is σ = 28614432. Its totient is φ = 14089920.

The previous prime is 21297817. The next prime is 21297851. The reversal of 21297849 is 94879212.

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

It is not a de Polignac number, because 21297849 - 2⁵ = 21297817 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 21297849.

It is not an unprimeable number, because it can be changed into a prime (21297869) 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, 26704 + ... + 27489.

It is an arithmetic number, because the mean of its divisors is an integer number (3576804).

Almost surely, 2^21297849 is an apocalyptic number.

It is an amenable number.

21297849 is a deficient number, since it is larger than the sum of its proper divisors (7316583).

21297849 is a wasteful number, since it uses less digits than its factorization.

21297849 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 54327.

The product of its digits is 72576, while the sum is 42.

The square root of 21297849 is about 4614.9592630921. The cubic root of 21297849 is about 277.1906527627.

The spelling of 21297849 in words is "twenty-one million, two hundred ninety-seven thousand, eight hundred forty-nine".