21470899 has 2 divisors, whose sum is σ = 21470900. Its totient is φ = 21470898.

The previous prime is 21470843. The next prime is 21470903. The reversal of 21470899 is 99807412.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 21470899 - 2⁹ = 21470387 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21470809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10735449 + 10735450.

It is an arithmetic number, because the mean of its divisors is an integer number (10735450).

Almost surely, 2^21470899 is an apocalyptic number.

21470899 is a deficient number, since it is larger than the sum of its proper divisors (1).

21470899 is an equidigital number, since it uses as much as digits as its factorization.

21470899 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 36288, while the sum is 40.

The square root of 21470899 is about 4633.6701436334. The cubic root of 21470899 is about 277.9393748380.

The spelling of 21470899 in words is "twenty-one million, four hundred seventy thousand, eight hundred ninety-nine".