21048665 has 8 divisors (see below), whose sum is σ = 27554688. Its totient is φ = 15308080.

The previous prime is 21048649. The next prime is 21048701. The reversal of 21048665 is 56684012.

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

It is not a de Polignac number, because 21048665 - 2⁴ = 21048649 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 191297 + ... + 191406.

It is an arithmetic number, because the mean of its divisors is an integer number (3444336).

Almost surely, 2^21048665 is an apocalyptic number.

It is an amenable number.

21048665 is a deficient number, since it is larger than the sum of its proper divisors (6506023).

21048665 is a wasteful number, since it uses less digits than its factorization.

21048665 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382719.

The product of its (nonzero) digits is 11520, while the sum is 32.

The square root of 21048665 is about 4587.8824091295. The cubic root of 21048665 is about 276.1053691706.

The spelling of 21048665 in words is "twenty-one million, forty-eight thousand, six hundred sixty-five".