21660334 has 4 divisors (see below), whose sum is σ = 32490504. Its totient is φ = 10830166.

The previous prime is 21660311. The next prime is 21660367. The reversal of 21660334 is 43306612.

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

It is a junction number, because it is equal to n+sod(n) for n = 21660299 and 21660308.

It is a congruent number.

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, 5415082 + ... + 5415085.

It is an arithmetic number, because the mean of its divisors is an integer number (8122626).

Almost surely, 2^21660334 is an apocalyptic number.

21660334 is a deficient number, since it is larger than the sum of its proper divisors (10830170).

21660334 is a wasteful number, since it uses less digits than its factorization.

21660334 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10830169.

The product of its (nonzero) digits is 2592, while the sum is 25.

The square root of 21660334 is about 4654.0663940258. The cubic root of 21660334 is about 278.7543904609.

Adding to 21660334 its reverse (43306612), we get a palindrome (64966946).

The spelling of 21660334 in words is "twenty-one million, six hundred sixty thousand, three hundred thirty-four".