21298047 has 8 divisors (see below), whose sum is σ = 28421760. Its totient is φ = 14186520.

The previous prime is 21298033. The next prime is 21298073. The reversal of 21298047 is 74089212.

It is a happy number.

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

It is not a de Polignac number, because 21298047 - 2⁸ = 21297791 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21297999 and 21298017.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21298447) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2454 + ... + 6972.

It is an arithmetic number, because the mean of its divisors is an integer number (3552720).

Almost surely, 2^21298047 is an apocalyptic number.

21298047 is a deficient number, since it is larger than the sum of its proper divisors (7123713).

21298047 is a wasteful number, since it uses less digits than its factorization.

21298047 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6093.

The product of its (nonzero) digits is 8064, while the sum is 33.

The square root of 21298047 is about 4614.9807150193. The cubic root of 21298047 is about 277.1915117474.

The spelling of 21298047 in words is "twenty-one million, two hundred ninety-eight thousand, forty-seven".