21535434 has 12 divisors (see below), whose sum is σ = 46660146. Its totient is φ = 7178472.

The previous prime is 21535433. The next prime is 21535477. The reversal of 21535434 is 43453512.

It can be written as a sum of positive squares in only one way, i.e., 11594025 + 9941409 = 3405^2 + 3153^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21535398 and 21535407.

It is not an unprimeable number, because it can be changed into a prime (21535433) 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 5 ways as a sum of consecutive naturals, for example, 598189 + ... + 598224.

Almost surely, 2^21535434 is an apocalyptic number.

21535434 is an abundant number, since it is smaller than the sum of its proper divisors (25124712).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21535434 is a wasteful number, since it uses less digits than its factorization.

21535434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1196421 (or 1196418 counting only the distinct ones).

The product of its digits is 7200, while the sum is 27.

The square root of 21535434 is about 4640.6286212107. The cubic root of 21535434 is about 278.2175634167.

Adding to 21535434 its reverse (43453512), we get a palindrome (64988946).

The spelling of 21535434 in words is "twenty-one million, five hundred thirty-five thousand, four hundred thirty-four".