21703634 has 4 divisors (see below), whose sum is σ = 32555454. Its totient is φ = 10851816.

The previous prime is 21703631. The next prime is 21703639. The reversal of 21703634 is 43630712.

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., 18105025 + 3598609 = 4255^2 + 1897^2 .

It is not an unprimeable number, because it can be changed into a prime (21703631) 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, 5425907 + ... + 5425910.

Almost surely, 2^21703634 is an apocalyptic number.

21703634 is a deficient number, since it is larger than the sum of its proper divisors (10851820).

21703634 is a wasteful number, since it uses less digits than its factorization.

21703634 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10851819.

The product of its (nonzero) digits is 3024, while the sum is 26.

The square root of 21703634 is about 4658.7159175034. The cubic root of 21703634 is about 278.9400144246.

The spelling of 21703634 in words is "twenty-one million, seven hundred three thousand, six hundred thirty-four".