21316742 has 8 divisors (see below), whose sum is σ = 33856056. Its totient is φ = 10031392.

The previous prime is 21316741. The next prime is 21316751. The reversal of 21316742 is 24761312.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21316741) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 313448 + ... + 313515.

It is an arithmetic number, because the mean of its divisors is an integer number (4232007).

Almost surely, 2^21316742 is an apocalyptic number.

21316742 is a deficient number, since it is larger than the sum of its proper divisors (12539314).

21316742 is a wasteful number, since it uses less digits than its factorization.

21316742 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 626982.

The product of its digits is 2016, while the sum is 26.

The square root of 21316742 is about 4617.0057396542. The cubic root of 21316742 is about 277.2725924181.

The spelling of 21316742 in words is "twenty-one million, three hundred sixteen thousand, seven hundred forty-two".