21434899 has 2 divisors, whose sum is σ = 21434900. Its totient is φ = 21434898.

The previous prime is 21434893. The next prime is 21434911. The reversal of 21434899 is 99843412.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21434899 - 2³ = 21434891 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21434891) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10717449 + 10717450.

It is an arithmetic number, because the mean of its divisors is an integer number (10717450).

Almost surely, 2^21434899 is an apocalyptic number.

21434899 is a deficient number, since it is larger than the sum of its proper divisors (1).

21434899 is an equidigital number, since it uses as much as digits as its factorization.

21434899 is an evil number, because the sum of its binary digits is even.

The product of its digits is 62208, while the sum is 40.

The square root of 21434899 is about 4629.7839042443. The cubic root of 21434899 is about 277.7839487281.

The spelling of 21434899 in words is "twenty-one million, four hundred thirty-four thousand, eight hundred ninety-nine".