21298873 has 2 divisors, whose sum is σ = 21298874. Its totient is φ = 21298872.

The previous prime is 21298861. The next prime is 21298877. The reversal of 21298873 is 37889212.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21132409 + 166464 = 4597^2 + 408^2 .

It is a cyclic number.

It is not a de Polignac number, because 21298873 - 2¹⁷ = 21167801 is a prime.

It is not a weakly prime, because it can be changed into another prime (21298877) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10649436 + 10649437.

It is an arithmetic number, because the mean of its divisors is an integer number (10649437).

Almost surely, 2^21298873 is an apocalyptic number.

It is an amenable number.

21298873 is a deficient number, since it is larger than the sum of its proper divisors (1).

21298873 is an equidigital number, since it uses as much as digits as its factorization.

21298873 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 48384, while the sum is 40.

The square root of 21298873 is about 4615.0702053165. The cubic root of 21298873 is about 277.1950951312.

The spelling of 21298873 in words is "twenty-one million, two hundred ninety-eight thousand, eight hundred seventy-three".