21168907 has 8 divisors (see below), whose sum is σ = 22325760. Its totient is φ = 20016360.

The previous prime is 21168899. The next prime is 21168911. The reversal of 21168907 is 70986112.

It is a happy number.

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

It is a cyclic number.

It is not a de Polignac number, because 21168907 - 2³ = 21168899 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21168967) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 16698 + ... + 17920.

It is an arithmetic number, because the mean of its divisors is an integer number (2790720).

Almost surely, 2^21168907 is an apocalyptic number.

21168907 is a deficient number, since it is larger than the sum of its proper divisors (1156853).

21168907 is a wasteful number, since it uses less digits than its factorization.

21168907 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2153.

The product of its (nonzero) digits is 6048, while the sum is 34.

The square root of 21168907 is about 4600.9680503129. The cubic root of 21168907 is about 276.6301283984.

The spelling of 21168907 in words is "twenty-one million, one hundred sixty-eight thousand, nine hundred seven".