21534911 has 2 divisors, whose sum is σ = 21534912. Its totient is φ = 21534910.

The previous prime is 21534899. The next prime is 21534967. The reversal of 21534911 is 11943512.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 21534911 - 2¹⁰ = 21533887 is a prime.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (21534991) 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, 10767455 + 10767456.

It is an arithmetic number, because the mean of its divisors is an integer number (10767456).

Almost surely, 2^21534911 is an apocalyptic number.

21534911 is a deficient number, since it is larger than the sum of its proper divisors (1).

21534911 is an equidigital number, since it uses as much as digits as its factorization.

21534911 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1080, while the sum is 26.

The square root of 21534911 is about 4640.5722707442. The cubic root of 21534911 is about 278.2153111756.

The spelling of 21534911 in words is "twenty-one million, five hundred thirty-four thousand, nine hundred eleven".