21098867 has 2 divisors, whose sum is σ = 21098868. Its totient is φ = 21098866.

The previous prime is 21098839. The next prime is 21098881. The reversal of 21098867 is 76889012.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21098867 - 2¹² = 21094771 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21098807) 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 as a sum of consecutive naturals, namely, 10549433 + 10549434.

It is an arithmetic number, because the mean of its divisors is an integer number (10549434).

Almost surely, 2^21098867 is an apocalyptic number.

21098867 is a deficient number, since it is larger than the sum of its proper divisors (1).

21098867 is an equidigital number, since it uses as much as digits as its factorization.

21098867 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 48384, while the sum is 41.

The square root of 21098867 is about 4593.3503023392. The cubic root of 21098867 is about 276.3247027418.

The spelling of 21098867 in words is "twenty-one million, ninety-eight thousand, eight hundred sixty-seven".