21165006 has 8 divisors (see below), whose sum is σ = 42330024. Its totient is φ = 7055000.

The previous prime is 21164989. The next prime is 21165007. The reversal of 21165006 is 60056112.

It is a happy number.

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

21165006 is an admirable number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21165007) 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, 1763745 + ... + 1763756.

It is an arithmetic number, because the mean of its divisors is an integer number (5291253).

Almost surely, 2^21165006 is an apocalyptic number.

21165006 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21165006 is a wasteful number, since it uses less digits than its factorization.

21165006 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3527506.

The product of its (nonzero) digits is 360, while the sum is 21.

The square root of 21165006 is about 4600.5440982562. The cubic root of 21165006 is about 276.6131349148.

The spelling of 21165006 in words is "twenty-one million, one hundred sixty-five thousand, six".