21164907 has 8 divisors (see below), whose sum is σ = 28282176. Its totient is φ = 14078792.

The previous prime is 21164863. The next prime is 21164929. The reversal of 21164907 is 70946112.

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 21164907 - 2¹⁶ = 21099371 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21164107) 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, 6153 + ... + 8954.

It is an arithmetic number, because the mean of its divisors is an integer number (3535272).

Almost surely, 2^21164907 is an apocalyptic number.

21164907 is a deficient number, since it is larger than the sum of its proper divisors (7117269).

21164907 is a wasteful number, since it uses less digits than its factorization.

21164907 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 15577.

The product of its (nonzero) digits is 3024, while the sum is 30.

The square root of 21164907 is about 4600.5333386467. The cubic root of 21164907 is about 276.6127036251.

The spelling of 21164907 in words is "twenty-one million, one hundred sixty-four thousand, nine hundred seven".