21535834 has 8 divisors (see below), whose sum is σ = 32381748. Its totient is φ = 10741920.

The previous prime is 21535781. The next prime is 21535837. The reversal of 21535834 is 43853512.

It can be written as a sum of positive squares in 2 ways, for example, as 13667809 + 7868025 = 3697^2 + 2805^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a junction number, because it is equal to n+sod(n) for n = 21535796 and 21535805.

It is not an unprimeable number, because it can be changed into a prime (21535837) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 11947 + ... + 13630.

Almost surely, 2^21535834 is an apocalyptic number.

21535834 is a deficient number, since it is larger than the sum of its proper divisors (10845914).

21535834 is a wasteful number, since it uses less digits than its factorization.

21535834 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26000.

The product of its digits is 14400, while the sum is 31.

The square root of 21535834 is about 4640.6717186201. The cubic root of 21535834 is about 278.2192859473.

The spelling of 21535834 in words is "twenty-one million, five hundred thirty-five thousand, eight hundred thirty-four".