21326434 has 4 divisors (see below), whose sum is σ = 31989654. Its totient is φ = 10663216.

The previous prime is 21326429. The next prime is 21326441. The reversal of 21326434 is 43462312.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in only one way, i.e., 21206025 + 120409 = 4605^2 + 347^2 .

It is a junction number, because it is equal to n+sod(n) for n = 21326399 and 21326408.

It is an unprimeable number.

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 as a sum of consecutive naturals, namely, 5331607 + ... + 5331610.

Almost surely, 2^21326434 is an apocalyptic number.

21326434 is a deficient number, since it is larger than the sum of its proper divisors (10663220).

21326434 is a wasteful number, since it uses less digits than its factorization.

21326434 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10663219.

The product of its digits is 3456, while the sum is 25.

The square root of 21326434 is about 4618.0552183793. The cubic root of 21326434 is about 277.3146082006.

Adding to 21326434 its reverse (43462312), we get a palindrome (64788746).

The spelling of 21326434 in words is "twenty-one million, three hundred twenty-six thousand, four hundred thirty-four".